- -------------------------------------------------------------------------------
- -------------------------------------------------------------------------------

                                 SCHEDULE 14A

                                (Rule 14a-101)

                    INFORMATION REQUIRED IN PROXY STATEMENT

                           SCHEDULE 14A INFORMATION

          Proxy Statement Pursuant to Section 14(a) of the Securities
                   Exchange Act of 1934 (Amendment No.    )

Filed by the Registrant [X]
Filed by a Party other than the Registrant [_]

Check the appropriate box:

[_]Preliminary Proxy Statement
[_]Confidential, for Use of the Commission Only (as permitted by Rule 14a-
6(e)(2))
[X]Definitive Proxy Statement
[_]Definitive Additional Materials
[_]Soliciting Material Pursuant to Rule 14a-11(c) or Rule 14a-12

                               ----------------

                          American Tower Corporation
               (Name of Registrant as Specified in Its Charter)

(Name of Person(s) Filing Proxy Statement, if Other Than the Registrant)
- -----------------------------------------------------------------------

Payment of Filing Fee (Check the appropriate box):

[X]No Fee Required.
[_]Fee computed on table below per Exchange Act Rules 14a-6(i)(1) and 0-11.

 (1)Title of each class of Securities to which transaction applies:
   -------------------------------------------------------------------

 (2)Aggregate number of securities to which transaction applies:
   -------------------------------------------------------------------

 (3) Per unit price or other underlying value of transaction computed
     pursuant to Exchange Act Rule 0-11(set forth the amount on which the
     filing fee is calculated and state how it was determined):
   -------------------------------------------------------------------

 (4)Proposed maximum aggregate value of transaction:
   -------------------------------------------------------------------

 (5)Total fee paid:
   -------------------------------------------------------------------

[_]Fee paid previously with preliminary materials.

[_Check]box if any part of the fee is offset as provided by Exchange Act Rule
  0-11(a)(2) and identify the filing for which the offsetting fee was paid
  previously. Identify the previous filing by registration statement number,
  or the form or schedule and the date of its filing.

 (1)Amount previously paid:
   -------------------------------------------------------------------

 (2)Form, Schedule or Registration Statement No.:
   -------------------------------------------------------------------

 (3)Filing Party:
   -------------------------------------------------------------------

 (4)Date Filed:
   -------------------------------------------------------------------

- -------------------------------------------------------------------------------
- -------------------------------------------------------------------------------


[LOGO OF AMERICAN TOWER]

                                                                 March 27, 2000

Dear Stockholder:

  It is a pleasure to invite you to the Company's 2000 Annual Meeting in
Boston, Massachusetts on Thursday, May 18, 2000 at 10:00 a.m., local time, at
the Corporate Board Room of American Tower Corporation, 116 Huntington Avenue,
11th Floor, Boston, Massachusetts 02116. Registration for the Meeting will
begin at 9:30 a.m. The official Notice of Meeting, proxy statement and form of
proxy are included with this letter. The matters listed in the Notice of
Meeting are described in detail in the proxy statement.

  The vote of every stockholder is important. Mailing your completed proxy
will not prevent you from voting in person at the meeting if you wish to do
so.

  Please sign, date and promptly mail your proxy. Your cooperation will be
greatly appreciated.

  Your Board of Directors and management look forward to greeting those
stockholders who are able to attend.

                                          Sincerely,

                                          /s/ Steven B. Dodge

                                          Steven B. Dodge
                                          Chairman of the Board, President and
                                          Chief Executive Officer


                          AMERICAN TOWER CORPORATION
                             116 Huntington Avenue
                          Boston, Massachusetts 02116

                               ----------------

                 NOTICE OF 2000 ANNUAL MEETING OF STOCKHOLDERS
                          TO BE HELD ON MAY 18, 2000

                               ----------------

To the Stockholders:

  The 2000 Annual Meeting of Stockholders (the "Annual Meeting") of American
Tower Corporation, a Delaware corporation ("American Tower" or the "Company"),
will be held at the Corporate Board Room of American Tower Corporation, 116
Huntington Avenue, 11th Floor, Boston, Massachusetts 02116 on Thursday, May
18, 2000 at 10:00 a.m., local time, to consider and act upon the following
matters:

    1. To elect ten directors, including two independent directors to be
  elected by the holders of Class A Common Stock, voting separately as a
  class, for the ensuing year or until their successors are elected and
  qualified;

    2. To approve an amendment to the Company's 1997 Stock Option Plan, as
  amended and restated, pursuant to which the number of shares of the
  Company's Class A Common Stock for which options may be granted would be
  increased by 9,000,000 from 15,000,000 so that options for an aggregate of
  24,000,000 shares of Common Stock may be issued under the Plan;

    3. To approve the stock option plan of the Company's wholly-owned
  subsidiary, ATC Teleports, Inc., pursuant to which options to purchase
  shares of common stock of that subsidiary may be granted;

    4. To approve, subject to consummation of the proposed merger, the stock
  option plan of Kline Iron & Steel Co., Inc., pursuant to which options to
  purchase shares of common stock of that subsidiary may be granted;

    5. To approve the adoption of the American Tower Corporation 2000
  Employee Stock Purchase Plan;

    6. To ratify the selection by the Board of Directors of Deloitte & Touche
  LLP as the Company's independent auditors for 2000; and

    7. To transact such other business as may properly come before the
  meeting or any adjournment or adjournments thereof.

  Stockholders of record at the close of business on March 22, 2000 are
entitled to notice of, and to vote at, the Annual Meeting. The stock transfer
books of the Company will remain open for the transfer of the Common Stock.
For a period of ten days prior to the Annual Meeting, a complete list of the
stockholders entitled to vote at the Annual Meeting will be available at the
offices of the Company for inspection by any stockholder of record for any
purpose germane to the Annual Meeting.

                                          By order of the Board of Directors,


                                          /s/ Jonathan R. Black
                                          Jonathan R. Black
                                          Secretary

Boston, Massachusetts
March 27, 2000

  WHETHER OR NOT YOU EXPECT TO ATTEND THE ANNUAL MEETING, PLEASE COMPLETE,
DATE AND SIGN THE ENCLOSED PROXY CARD AND PROMPTLY MAIL THE PROXY CARD IN THE
ENCLOSED ENVELOPE IN ORDER TO ASSURE REPRESENTATION OF YOUR SHARES AT THE
ANNUAL MEETING. NO POSTAGE NEED BE AFFIXED IF THE PROXY CARD IS MAILED WITHIN
THE UNITED STATES.


                          AMERICAN TOWER CORPORATION
                             116 Huntington Avenue
                          Boston, Massachusetts 02116

                                PROXY STATEMENT
                  FOR THE 2000 ANNUAL MEETING OF STOCKHOLDERS

                          To be held on May 18, 2000

                              GENERAL INFORMATION

  This Proxy Statement is furnished in connection with the solicitation of
proxies by the Board of Directors (the "Board of Directors") of American Tower
Corporation ("American Tower" or the "Company"), a Delaware corporation, for
use at the 2000 Annual Meeting of Stockholders to be held on May 18, 2000 or
at any adjournment or postponement thereof.

  The Company's Annual Report to Stockholders for the fiscal year ended
December 31, 1999 is being mailed to stockholders with the mailing of this
Proxy Statement on or about March 31, 2000.

  All costs of solicitation of proxies will be borne by the Company. In
addition to solicitations by mail, the Company's directors, officers and
regular employees, without additional remuneration, may solicit proxies by
telephone, telecopy and personal interviews. Brokers, banks, custodians and
other fiduciaries will be requested to forward proxy soliciting material to
the beneficial owners of stock held of record by such persons, and the Company
will reimburse them for their reasonable out-of-pocket expenses incurred in
connection with the distribution of such proxy materials.

Revocability of Proxies

  Any stockholder giving a proxy has the power to revoke it at any time before
it is exercised by delivering to the Secretary of the Company at its principal
executive office located at 116 Huntington Avenue, Boston, Massachusetts 02116
a written notice of revocation or another duly executed proxy bearing a later
date. A stockholder may also revoke his or her proxy by attending the Annual
Meeting and voting in person.

Record Date, Voting and Share Ownership

  The Company has three classes of common stock issued and outstanding: Class
A Common Stock, $.01 par value per share, Class B Common Stock, $.01 par value
per share, and Class C Common Stock, $.01 par value per share (the Class A
Common Stock, the Class B Common Stock and the Class C Common Stock are
collectively referred to as the "Common Stock").

  With respect to the matters submitted for vote at the Annual Meeting, each
share of Class A Common Stock is entitled to one vote, and each share of Class
B Common Stock is entitled to ten votes. The Class C Common Stock is not
entitled to vote on the matters submitted at the Annual Meeting. Except with
respect to the election of two of the directors, the Class A Common Stock and
the Class B Common Stock will vote as a single class in regards to the matters
submitted at the Annual Meeting. With respect to the election of directors,
the holders of Class A Common Stock are entitled by class vote, exclusive of
all other stockholders, to elect two independent directors (the "Independent
Directors"). On March 22, 2000, there were outstanding and entitled to vote
146,248,600 shares of Class A Common Stock and 8,361,342 shares of Class B
Common Stock.

  The presence at the Annual Meeting, in person or by proxy, of the holders of
a majority of the votes represented by the Class A Common Stock and the Class
B Common Stock issued and outstanding on March 22, 2000 will constitute a
quorum for the transaction of business at the Annual Meeting. For the separate
vote of the Class A Common Stock, quorum will be the presence in person or by
proxy of the holders of a


majority of the votes represented by the Class A Common Stock. A proxy in the
enclosed form, if received in time for voting and not revoked, will be voted
at the Annual Meeting in accordance with the instructions contained therein.
Where a choice is not so specified, the shares represented by the proxy will
be voted "for" the election of the nominees for directors listed herein and in
favor of the other matters set forth in the Notice of Annual Meeting
accompanying this Proxy Statement.

  Votes cast at the Annual Meeting will be tabulated by a person duly
appointed to act as an inspector of election for the Annual Meeting. The
inspector of election will treat shares represented by a properly signed and
returned proxy as present at the Annual Meeting for purposes of determining a
quorum, without regard to whether the proxy is marked as casting a vote or
abstaining. Likewise, the inspector of election will treat shares represented
by "broker non-votes" as present for purposes of determining a quorum,
although such shares may not be voted on any matter for which the record
holder of such shares lacks authority to act. Broker non-votes are proxies
with respect to shares held in record name by brokers or nominees, as to which
(1) instructions have not been received from the beneficial owners or persons
entitled to vote, (2) the broker or nominee does not have discretionary voting
power under applicable national securities exchange rules or the instrument
under which it serves in such capacity, and (3) the record holder has
indicated on the proxy card or otherwise notified the Company that it does not
have authority to vote such shares on that matter. Abstentions and broker non-
votes do not affect the election of directors or approval of the other items
discussed in this Proxy Statement.

                                       2


Security Ownership of Certain Beneficial Owners and Management

  The following sets forth certain information known to American Tower as of
March 1, 2000 with respect to the shares of Common Stock that are beneficially
owned as of such date by (1) each director, (2) each executive officer, (3)
all directors and executive officers as a group, and (4) each person known by
the Company to own more than 5% of the outstanding Common Stock. The number of
shares beneficially owned by each person is determined according to the rules
of the Securities and Exchange Commission (the "Commission"), and the
information is not necessarily indicative of beneficial ownership for any
other purpose. Under these rules, beneficial ownership includes any shares as
to which the individual or entity has sole or shared voting power or
investment power and also any shares which the individual or entity has the
right to acquire within sixty days of March 1, 2000 through the exercise of an
option, conversion feature or similar right. Except as noted below, each
holder has sole voting and investment power with respect to all shares of
Common Stock listed as owned by that holder.



                                                           Percent of  Percent of
                            Number   Percent of Percent of   Common   Total Voting
                          of Shares   Class A    Class B     Stock       Power
                          ---------- ---------- ---------- ---------- ------------
                                                       
Directors and Executive
 Officers
Steven B. Dodge(1)......   7,459,710     *        71.73       4.70       28.94
Thomas H. Stoner(2).....   1,441,653     *        16.78        *          6.13
Alan L. Box(3)..........     966,396     *          --         *           *
Arnold L. Chavkin
 (CEA)(4)...............   6,298,816    2.65        --        4.01        1.69
James S. Eisenstein(5)..     394,931     *         1.17        *           *
Dean H. Eisner(6).......   1,886,055    1.29        --        1.20         *
Jack D. Furst(7)........      24,364     *          --         *           *
J. Michael Gearon,
 Jr.(8).................   4,017,868    2.75        --        2.56        1.75
Fred R. Lummis(9).......   1,356,749     *          --         *           *
Randall T. Mays (Clear
 Channel)(10)...........   9,029,717    6.18        --        5.76        3.93
Steven J.
 Moskowitz(11)..........     106,000     *          --         *           *
Douglas C. Wiest(12)....     156,557     *          --         *           *
Maggie Wilderotter(13)..      10,000     *          --         *           *
Joseph L. Winn(14)......     577,120     *         4.49        *          1.74
All executive officers
 and directors as a
 group (fourteen
 persons)(15)...........  33,725,936   15.12      88.69      21.01       44.88
Five Percent
 Stockholders
Wellington Management
 Company, LLP(16).......  16,507,240   11.30        --       10.52        7.18
FMR Corp.(17)...........   8,959,384    6.13        --        5.71        3.90
Putnam Investments,
 Inc.(18)...............  11,696,754    8.01        --        7.46        5.09

- --------
  * Less than 1%.
 (1) Mr. Dodge is Chairman of the Board of Directors, President and Chief
     Executive Officer. His address is 116 Huntington Avenue, Boston,
     Massachusetts 02116. Includes 10,030 shares of Class A Common Stock and
     3,561,911 shares of Class B Common Stock owned by Mr. Dodge, an aggregate
     of 25,050 shares of Class A Common Stock and 33,915 shares of Class B
     Common Stock owned by three trusts for the benefit of Mr. Dodge's
     children, 66,720 shares of Class A Common Stock and 2,000,000 shares of
     Class B Common Stock owned by a limited liability company, of which Mr.
     Dodge is the sole member, 5,000 shares of Class A Common Stock owned by
     Mr. Dodge's wife and 5,000 shares of Class B Common Stock owned by a
     charitable foundation of which Mr. and Mrs. Dodge are trustees. Mr.
     Dodge's wife and a third party serve as co-trustees for the three trusts.
     Mr. Dodge disclaims beneficial ownership of all shares owned by such
     trusts, the charitable foundation and his wife. Does not include 170
     shares of Class A Common Stock held by Thomas S. Dodge, an adult child of
     Mr. Dodge, with respect to which Mr. Dodge disclaims beneficial
     ownership. Includes options to purchase an aggregate of 1,432,084 shares
     of Class B

                                       3


    Common Stock and 320,000 shares of Class A Common Stock that are vested.
    Does not include options to purchase an aggregate of 1,169,173 shares of
    Class B Common Stock and 1,580,000 shares of Class A Common Stock that are
    unvested.
 (2) Mr. Stoner is Chairman of the Executive Committee of the Board of
     Directors. His address is 116 Huntington Avenue, Boston, Massachusetts
     02116. Includes 31,311 shares of Class B Common Stock owned by his wife,
     an aggregate of 1,316,285 shares of Class B Common Stock and 2,500 shares
     of Class A Common Stock owned by trusts of which he and/or certain other
     persons are trustees, and 56,988 shares of Class B Common Stock and
     10,245 shares of Class A Common Stock to be issued upon conversion of
     convertible notes owned by a charitable foundation of which Mr. Stoner
     serves as an officer. Mr. Stoner disclaims beneficial ownership of
     278,853 shares of Class B Common Stock and 2,500 shares of Class A Common
     Stock owned by the charitable foundation and such trusts. Does not
     include 93,852 shares of Class A Common Stock and 28,727 shares of Class
     B Common Stock owned by Mr. Stoner's adult children, with respect to
     which Mr. Stoner disclaims beneficial ownership. Includes options to
     purchase an aggregate of 24,324 shares of Class A Common Stock that are
     vested. Does not include options to purchase an aggregate of 66,215
     shares of Class A Common Stock that are unvested.
 (3) Mr. Box is an Executive Vice President and a director. His address is 116
     Huntington Avenue, Boston, Massachusetts 02116. Includes 698,858 shares
     of Class A Common Stock owned by Mr. Box, 2,070 shares of Class A Common
     Stock owned by two trusts for the benefit of Mr. Box's children and
     options to purchase an aggregate of 265,468 shares of Class A Common
     Stock that are vested. Does not include options to purchase an aggregate
     of 370,310 shares of Class A Common Stock that are unvested.
 (4) Mr. Chavkin is a director. His address is 116 Huntington Avenue, Boston,
     Massachusetts 02116. Mr. Chavkin, as a general partner of Chase Capital
     Partners ("CCP"), which indirectly controls Chase Equity Associates, LLC
     ("CEA"), may be deemed to own beneficially shares held by CEA and Chase
     Manhattan Capital, L.P. ("Chase Capital"), an affiliate of Mr. Chavkin.
     Includes 21,719 shares of Class A Common Stock and 2,422,804 shares of
     Class C Common Stock owned by CEA and 3,829,969 shares of Class A Common
     Stock owned by Chase Capital. Mr. Chavkin disclaims beneficial ownership
     of such shares. The address of CCP and CEA is 380 Madison Avenue, 12th
     Floor, New York, New York 10017. Includes options to purchase an
     aggregate of 24,324 shares of Class A Common Stock that are vested.
     Does not include options to purchase an aggregate of 66,215 shares of
     Class A Common Stock that are unvested.
 (5) Mr. Eisenstein is Executive Vice President--Corporate Development. His
     address is 116 Huntington Avenue, Boston, Massachusetts 02116. Includes
     25,000 shares of Class A Common Stock owned by Mr. Eisenstein. Includes
     options to purchase an aggregate of 99,450 shares of Class B Common Stock
     and of 270,481 shares of Class A Common Stock that are vested. Does not
     include options to purchase an aggregate of 24,861 shares of Class B
     Common Stock and 229,949 shares of Class A Common Stock that are
     unvested.
 (6) Mr. Eisner is a director. He is Vice President, Business Development and
     Planning of Cox Enterprises, Inc., an affiliate of the former principal
     member of TeleCom Towers, L.L.C. ("Telecom"), which merged with the
     Company in 1999. Mr. Eisner's address is 1400 Lake Hearn Drive, N.E.,
     Atlanta, GA 30319. Includes 1,881,055 shares of Class A Common Stock
     owned by Cox Telecom Towers, Inc., an affiliate of Cox Enterprises, Inc.,
     which may be deemed to be beneficially owned by Mr. Eisner. Includes
     options to purchase an aggregate of 5,000 shares of Class A Common Stock
     that are vested. Does not include options to purchase an aggregate of
     45,000 shares of Class A Common Stock that are unvested.
 (7) Mr. Furst is a director. His address is 200 Crescent Court, Suite 1600,
     Dallas, Texas 75201-6950. Includes 19,364 shares of Class A Common Stock
     owned by Mr. Furst. Mr. Furst, as a shareholder of the general partner
     and as a limited partner of Hicks Muse & Co. Partners, L.P. ("Hicks
     Muse") may be deemed to own beneficially shares held by Hicks Muse.
     Includes options held by Hicks Muse to purchase an aggregate of 5,000
     shares of Class A Common Stock that are vested. Does not include options
     held by Hicks Muse to purchase an aggregate of 45,000 shares of Class A
     Common Stock that are unvested. Mr. Furst disclaims beneficial ownership
     of the shares held by Hicks Muse, except to the extent of his pecuniary
     interest therein.

                                       4


 (8) Mr. Gearon is an Executive Vice President and a director. His address is
     116 Huntington Avenue, Boston, Massachusetts 02116. Includes 738,833
     shares of Class A Common Stock owned directly by Mr. Gearon and an
     aggregate of 3,165,254 shares of Class A Common Stock owned by limited
     partnerships that Mr. Gearon controls. Does not include 300,000 shares of
     Class A Common Stock held by a trust for the benefit of Mr. Gearon's
     children, of which J. Michael Gearon, Sr. is the trustee. Mr. Gearon
     disclaims beneficial ownership in all shares owned by such trust.
     Includes options to purchase an aggregate of 113,781 shares of Class A
     Common Stock that are vested. Does not include options to purchase an
     aggregate of 320,670 shares of Class A Common Stock that are unvested.
 (9) Mr. Lummis is a director. His address is 3411 Richmond Avenue, Suite 400,
     Houston, Texas 77046. Includes 69,105 shares of Class A Common Stock
     owned by Mr. Lummis, an aggregate of 256,252 shares of Class A Common
     Stock owned by trusts of which he is trustee, 524,349 shares of Class A
     Common Stock owned by Summit Capital, Inc. ("Summit Capital"), an
     affiliate of Mr. Lummis by reason of Mr. Lummis' 50% ownership of its
     common stock. Mr. Lummis disclaims beneficial ownership of all shares
     owned by the trusts and Summit Capital, except to the extent of his
     pecuniary interest therein. Includes options to purchase an aggregate of
     507,043 shares of Class A Common Stock that are vested. Does not include
     options to purchase an aggregate of 64,999 shares of Class A Common Stock
     that are unvested.
(10) Mr. Mays, the Chief Financial Officer and an Executive Vice President of
     Clear Channel Communications, Inc. ("Clear Channel"), is a director. His
     address is P.O. Box 659512, San Antonio, Texas 78265-9512. Clear Channel
     owns all of the shares of Class A Common Stock shown in the table. Mr.
     Mays disclaims beneficial ownership of Clear Channel's ownership of such
     shares. Includes options to purchase an aggregate of 10,000 shares of
     Class A Common Stock that are vested. Does not include options to
     purchase an aggregate of 65,000 shares of Class A Common Stock that are
     unvested.
(11) Mr. Moskowitz is Executive Vice President--Marketing and General Manager
     of the Northeast region. His address is 116 Huntington Avenue, Boston,
     Massachusetts 02116. Includes 28,000 shares of Class A Common Stock owned
     by Mr. Moskowitz. Includes options to purchase an aggregate of 78,000
     shares of Class A Common Stock that are vested. Does not include options
     to purchase an aggregate of 232,000 shares of Class A Common Stock that
     are unvested.
(12) Mr. Wiest is the Chief Operating Officer. His address is 116 Huntington
     Avenue, Boston, Massachusetts 02116. Includes 35,556 shares of Class A
     Common Stock owned by Mr. Wiest. Includes options to purchase an
     aggregate of 121,000 shares of Class A Common Stock that are vested. Does
     not include options to purchase an aggregate of 304,000 shares of Class A
     Common Stock that are unvested.
(13) Ms. Wilderotter is a director. Her address is 116 Huntington Avenue,
     Boston, Massachusetts 02116. Includes options to purchase an aggregate of
     10,000 shares of Class A Common Stock that are vested. Does not include
     options to purchase an aggregate of 65,000 shares of Class A Common Stock
     that are unvested.
(14) Mr. Winn is the Treasurer and Chief Financial Officer. His address is 116
     Huntington Avenue, Boston, Massachusetts 02116. Includes 2,000 shares of
     Class A Common Stock and 230,657 shares of Class B Common Stock owned
     individually by Mr. Winn and 100 shares of Class A Common Stock held for
     the benefit of his children. Includes options to purchase an aggregate of
     152,315 shares of Class B Common Stock and 192,048 shares of Class A
     Common Stock that are vested. Does not include options to purchase an
     aggregate of 49,014 shares of Class B Common Stock and 503,032 shares of
     Class A Common Stock that are unvested.
(15) Includes all shares stated to be owned in the preceding notes.
(16) The address of Wellington Management Company, LLP ("Wellington") is 75
     State Street, Boston, Massachusetts 02109. Based on Wellington's Schedule
     13G dated February 1, 2000, Wellington has sole voting power over 0
     shares of Class A Common Stock, shared voting power over 11,330,780
     shares of Class A Common Stock, sole dispositive power over 0 shares of
     Class A Common Stock and shared dispositive power over 16,316,540 shares
     of Class A Common Stock.

                                       5


(17) The address of FMR Corp. ("FMR") is 82 Devonshire Street, Boston,
     Massachusetts 02109. Based on FMR's Schedule 13G dated February 11, 2000,
     FMR has sole voting power over 20,000 shares of Class A Common Stock,
     shared voting power over 0 shares of Class A Common Stock, sole
     dispositive power over 8,959,384 shares of Class A Common Stock and
     shared dispositive power over 0 shares of Class A Common Stock.
(18) The address of Putnam Investments, Inc. ("PI") is One Post Office Square,
     Boston, Massachusetts 02109. PI, which is a wholly owned subsidiary of
     Marsh & McLennan Companies, Inc. ("MMC"), wholly owns two registered
     investment advisers: Putnam Investment Management, Inc. ("PIM"), which is
     the investment adviser to the Putnam family of mutual funds, and The
     Putnam Advisory Company, Inc. ("PAC"), which is the investment advisor to
     Putnam's institutional clients. Both subsidiaries have dispositive power
     over the shares as investment managers, but each of the mutual fund's
     trustees have voting power over the shares held by each fund, and PAC has
     shared voting power over the shares held by Putnam's institutional
     clients. MMC has sole voting power over 0 shares of Class A Common Stock,
     shared voting power over 0 shares of Class A Common Stock, sole
     dispositive power over 0 shares of Class A Common Stock and shared
     dispositive power over 0 shares of Class A Common Stock. PIM has sole
     voting power over 0 shares of Class A Common Stock, shared voting power
     over 0 shares of Class A Common Stock, sole dispositive power over 0
     shares of Class A Common Stock and shared dispositive power over
     11,315,774 shares of Class A Common Stock. PAC has sole voting power over
     0 shares of Class A Common Stock, shared voting power over 89,600 shares
     of Class A Common Stock, sole dispositive power over 0 shares of Class A
     Common Stock and shared dispositive power over 380,980 shares of Class A
     Common Stock. PI has sole voting power over 0 shares of Class A Common
     Stock, shared voting power over 89,600 shares of Class A Common Stock,
     sole dispositive power over 0 shares of Class A Common Stock and shared
     dispositive power over 11,696,754 shares of Class A Common Stock. All of
     the above information is based on PI's Schedule 13G, dated February 7,
     2000.

                                       6


                                    ITEM 1

                             ELECTION OF DIRECTORS

  The Board of Directors currently consists of ten directors. The Board of
Directors has nominated for election as directors at the Annual Meeting the
ten incumbent directors listed below. Persons elected at the meeting will hold
office until the 2001 Annual Meeting or until their successors are elected and
qualified, subject to earlier retirement, resignation or removal. If any of
the above nominees become unavailable to serve, the shares represented by
proxies will be voted for the election of such other person as may be
recommended by the Board of Directors or management. Unless otherwise
instructed, proxies received by the Company will be voted FOR the nominees
listed below.

Required Vote

  Except for the election of the Independent Directors, a plurality of the
votes properly cast by or on behalf of the holders of Class A Common Stock and
Class B Common Stock at the Annual Meeting, voting as a single class, is
required for the election of directors. For the election of the Independent
Directors, votes properly cast by or on behalf of the holders of a plurality
of Class A Common Stock at the Annual Meeting, voting as a separate class, is
required.

  Mr. Lummis and Ms. Wilderotter have been nominated as the Independent
Directors.

  The Board of Directors recommends that the stockholders vote FOR the
election of each of the nominees listed below to serve as directors of the
Company until the next Annual Meeting or until their successors are elected
and qualified.

  Set forth below are the name and age of each director, his or her principal
occupation and business experience during the past five years and the names of
other publicly traded companies of which he/she serves as a director as of
March 1, 2000.

                  Principal Occupations and Business Experience During the
Nominee           Past Five Years

Steven B. Dodge   Mr. Dodge has served as the Chairman of the Board of
 Age 54           Directors, President and Chief Executive Officer since
                  American Tower's organization. Mr. Dodge was also the
                  Chairman of the Board of Directors, President and Chief
                  Executive Officer of American Radio Systems ("American
                  Radio"), a position he occupied since its founding on
                  November 1, 1993 until June 1998. In June 1998, American
                  Radio became a subsidiary of CBS, and American Tower became
                  an independent public company through the distribution by
                  American Radio to its securityholders of all of its shares
                  in American Tower (the "ATC Separation"). Mr. Dodge was the
                  founder in 1988 of Atlantic Radio, which was one of the
                  predecessor entities of American Radio. Mr. Dodge also
                  serves as a director of Weblink Wireless, Inc., TD
                  Waterhouse Group, Inc. and Nextel Partners, Inc.

Alan L. Box
 Age 48           Mr. Box has served as an Executive Vice President since
                  March 1998 and has been a director since its organization.
                  Mr. Box served as Chief Operating Officer from June 1997 to
                  March 1998, at which time he assumed his present role as the
                  Executive Vice President responsible for the Internet,
                  voice, data and video transmission business. Mr. Box also
                  was an Executive Vice President and a director of American
                  Radio from April 1997, when EZ Communications, Inc. ("EZ")
                  merged into American Radio (the "EZ Merger"), until
                  consummation of the ATC Separation. Prior to the EZ Merger,
                  Mr. Box had been the Chief Executive Officer of EZ, a
                  company he formed in 1974.

                                       7


    Nominee      Principal Occupations and Business Experience During the Past
                                          Five Years

                  Mr. Chavkin has been a member of the Executive Committee,
Arnold L.         the Audit Committee and the Compensation Committee since
Chavkin           November 1997. Mr. Chavkin was the Chairman of the Audit
 Age 48           Committee of American Radio from its founding until
                  consummation of the ATC Separation and of the Audit
                  Committee of American Radio from November 1997 until
                  November 1998. Mr. Chavkin is a general partner of CCP,
                  which indirectly controls CEA, a stockholder of American
                  Tower, and the President of Chemical Investments, Inc.,
                  where he has served since 1991. Mr. Chavkin is also a
                  director of R&B Falcon Corporation, Wireless One, Inc. and
                  Patina Oil & Gas Corporation.

Dean H. Eisner    Mr. Eisner has been a director since the merger with TeleCom
 Age 42           on February 26, 1999. Since May 1995, Mr. Eisner has served
                  as Vice President, Business Development and Planning of Cox
                  Enterprises, Inc., an affiliate of Cox Telecom Towers, Inc.,
                  the former principal member of TeleCom. He joined COX
                  Enterprises, Inc. in 1993.

Jack D. Furst
 Age 41           Mr. Furst has been a director since the merger with
                  OmniAmerica on February 25, 1999. Mr. Furst was Chairman of
                  OmniAmerica prior to the merger. He has been a partner of
                  Hicks, Muse, Tate & Furst, Incorporated, an affiliate of
                  OmniAmerica's former principal stockholder since 1989. Mr.
                  Furst currently serves as a director of Cooperative
                  Computing, Inc., Hedstrom Corp., Globix Corporation,
                  International Wire Group, Inc., Viasystems, Inc., Home
                  Interiors & Gifts, Inc., LLS Corp. and Triton Energy
                  Limited.

J. Michael        Mr. Gearon has served as an Executive Vice President and has
Gearon, Jr.       been a director since the merger with Gearon & Co., Inc.
 Age 35           ("Gearon") on January 22, 1998. Mr. Gearon had been the
                  principal stockholder and Chief Executive Officer of Gearon
                  since September, 1991. Mr. Gearon currently serves as a
                  director of TV Azteca.

Fred R. Lummis
 Age 46           Mr. Lummis has been a member of the Audit Committee since
                  the merger with American Tower Corporation ("Old ATC"), an
                  unaffiliated company, on June 8, 1998. Mr. Lummis was the
                  Chairman, Chief Executive Officer and President of Old ATC.
                  Since June 1998, Mr. Lummis has also served as the Chairman,
                  President and Chief Executive Officer of Advantage Outdoor
                  Company, L.P. Mr. Lummis has been the President of Summit
                  Capital, a private investment firm and a substantial
                  stockholder of Old ATC, since June 1990. Mr. Lummis
                  currently serves on the board of several private companies
                  and is a trustee of the Baylor College of Medicine.

Randall T. Mays   Mr. Mays has been the Chairman of the Audit Committee since
 Age 34           November 1998 and a director since the merger with Old ATC
                  on June 8, 1998. Mr. Mays has served as Chief Financial
                  Officer and Executive Vice President of Clear Channel, which
                  had been the principal stockholder of Old ATC, since
                  February 1997, prior to which he had served as a Vice
                  President and Treasurer since joining Clear Channel in 1993.

Thomas H.
Stoner            Mr. Stoner has been the Chairman of the Executive Committee
 Age 65           and the Compensation Committee since November 1997. Mr.
                  Stoner was the Chairman of the Executive Committee and the
                  Compensation Committee of American Radio from its founding
                  until consummation of the ATC Separation. In 1965, Mr.
                  Stoner founded Stoner Broadcasting Systems, Inc. one of the
                  predecessors of American Radio. Mr. Stoner is a director of
                  Gaylord Container Corporation and a trustee of the
                  Chesapeake Bay Foundation.

                                       8


    Nominee      Principal Occupations and Business Experience During the Past
                                          Five Years

Maggie            Ms. Wilderotter has been a member of the Compensation
Wilderotter       Committee since November 1998 and a director since August
 Age 45           1998. Ms. Wilderotter is the President and Chief Executive
                  Officer of Wink Communications ("Wink"), a California
                  company that develops technology for adding simple
                  interactivity and graphics to mass-market consumer
                  electronic products. Before joining Wink in 1997, Ms.
                  Wilderotter was the Executive Vice President of National
                  Operations for AT&T Wireless Services, Inc., and Chief
                  Executive Officer of AT&T's Aviation Communications
                  Division. Ms. Wilderotter has also served as Senior Vice
                  President of McCaw Cellular Communications, Inc. and
                  Regional President of its California, Arizona, New Mexico,
                  Nevada and Hawaii Region. Ms. Wilderotter serves on the
                  boards of Airborne Express, Electric Lightwave, Inc.,
                  Gaylord Entertainment, Allied Riser Communications Corp.,
                  the California Cable Television Association and the
                  California Chamber of Commerce and she is a trustee of Holy
                  Cross College in Worcester, Massachusetts.

Board and Committee Meetings

  During the fiscal year ended December 31, 1999, the Board of Directors held
four regular meetings, one special meeting by telephone and took actions by
written consent. Each of the current directors who was then in office attended
at least 75% of the aggregate number of meetings of the Board of Directors and
all committees thereof on which such director served. The committees of the
Board of Directors consist of an Audit Committee, a Compensation Committee and
an Executive Committee. During the fiscal year ended December 31, 1999, the
Compensation Committee held two meetings, the Executive Committee held one
meeting and the Audit Committee held three meetings. The Company does not have
a nominating committee.

  The Audit Committee currently consists of Messrs. Mays (Chairman), Chavkin
and Lummis. The functions of the Audit Committee are to review and report to
the Board of Directors with respect to the selection and the terms of the
engagement of the independent auditors and to maintain communications among
the Board of Directors, such independent auditors and the internal accounting
staff with respect to accounting and audit procedures, the implementation of
recommendations by such independent auditors, the adequacy of internal
controls and related matters.

  The Compensation Committee currently consists of Messrs. Stoner (Chairman)
and Chavkin and Ms. Wilderotter. The Compensation Committee provides
recommendations to the Board of Directors regarding compensation strategy and
programs and administers the Stock Option Plan, including the grant of stock
options thereunder. The Compensation Committee is also responsible for
establishing and modifying the compensation, including incentive compensation,
of all corporate officers, recommending adoptions of, and amendment to, all
stock option and other employee benefit plans and arrangements, and the
engagement of, terms of any employment agreements and arrangements with, and
termination of, all corporate officers.

  The Executive Committee currently consists of Messrs. Stoner (Chairman),
Dodge and Chavkin. Between meetings of the Board of Directors, the Executive
Committee exercises all the powers of the Board of Directors in the management
and direction of the business and affairs of the Company, except as provided
otherwise by law, resolutions of the Board of Directors or the Restated
Certificate of Incorporation or By-laws.

Director Compensation

  The Company's nonemployee directors received options to purchase 25,000
shares of Class A Common Stock during the fiscal year ended December 31, 1999.
In March 1999, Messrs. Furst and Eisner each received an initial option to
purchase 25,000 shares of Class A Common Stock. All of the options granted to
nonemployee directors in 1999 are exercisable in 20% cumulative annual
increments commencing one year from the date of grant and expiring at the end
of ten years. The nonemployee directors also receive $2,500 for attending each
board meeting, $1,000 for each committee on which he or she serves, and $3,000
for each committee on which he or she serves as chairperson.

                                       9


Information Regarding Executive Officers

  The following table sets forth certain information concerning each
individual, other than Mr. Dodge, who currently serves as an executive
officer, including such person's business experience during at least the past
five years. Executive officers are appointed by the Board of Directors and
serve at the discretion of the Board. There are no family relationships among
the executive officers, nor are there any arrangements or understandings
between any executive officer and another person pursuant to which he was
selected as an officer except as may be hereinafter described.

      Name          Principal Occupations and Business Experience During the
                                         Past Five Years

                  James S. Eisenstein is the Executive Vice President--
James S.          Corporate Development. Mr. Eisenstein has overall
Eisenstein        responsibility for seeking out acquisition and development
 Age 41           opportunities. Mr. Eisenstein helped form American Tower in
                  the summer of 1995. From 1990 to 1995, he was Chief
                  Operating Officer for Amaturo Group Ltd., a broadcast
                  company operating 11 radio stations and four broadcasting
                  towers, several of which were purchased by American Radio.
                  Mr. Eisenstein serves on the Board of Directors of the
                  Personal Communications Industry Association, the leading
                  international trade association representing the wireless
                  communications industry.

Steven J.
Moskowitz         Steven J. Moskowitz is the Executive Vice President--
 Age 36           Marketing and General Manager of the Northeast Region. Mr.
                  Moskowitz joined the Company in January 1998, initially as a
                  Vice President and General Manager of the Northeast Region,
                  and assumed his current position in March 1999. Prior to
                  joining American Tower, Mr. Moskowitz had served as a Vice
                  President of The Katz Media Group, the largest broadcast
                  media representation firm in the U.S., since 1989.

Douglas C.        Douglas C. Wiest is the Chief Operating Officer. Mr. Wiest
Wiest             jointed the Company in February 1998, initially as the Chief
 Age 47           Operating Officer of Gearon Communications, and assumed his
                  current position in March 1998. Prior to joining American
                  Tower, Mr. Wiest had been Regional Vice President of
                  Engineering and Operations for Nextel's southern region
                  since 1993.

Joseph L. Winn
 Age 48           Joseph L. Winn is the Chief Financial Officer and Treasurer.
                  Mr. Winn was also Treasurer, Chief Financial Officer and a
                  director of American Radio since its founding in 1993 until
                  consummation of the ATC Separation.

                                      10


                            EXECUTIVE COMPENSATION

  The following table provides certain information concerning compensation
earned by the Chief Executive Officer and the four other most highly
compensated executive officers who received compensation in excess of $100,000
in 1999.

Summary Compensation Table



                                                                  Long-Term
                                  Annual Compensation            Compensation
                          -------------------------------------- ------------
                                                                    Shares
   Name and Principal                               Other Annual  Underlying     All Other
        Position          Year    Salary(a)  Bonus  Compensation   Options    Compensation(b)
   ------------------     ----    --------- ------- ------------ ------------ ---------------
                                                            
Steven B. Dodge.........  1997(c) $502,338      --      --          100,000       $ 1,719
 Chairman of the Board,
  President               1998(c) $370,349      --      --        3,300,000       $ 5,946
 and Chief Executive
  Officer                 1999    $412,363      --      --          300,000       $ 6,736

Douglas C. Wiest........  1998    $211,007      --      --          365,001       $ 4,576
 Chief Operating Officer  1999    $318,001      --      --           60,000       $ 8,400

Joseph L. Winn..........  1997(c) $352,329  $40,000     --           35,000       $12,876
 Treasurer and Chief
  Financial               1998(c) $298,779      --      --          610,000       $13,210
 Officer                  1999    $288,268      --      --           60,000       $12,996

James S. Eisenstein.....  1997    $212,367      --      --           27,310       $12,656
 Executive Vice
  President--             1998    $204,850  $50,000     --          150,000       $13,295
 Corporate Development    1999    $263,263      --      --           50,000       $11,130

J. Michael Gearon, Jr...  1998    $176,135      --      --          334,451       $   346
 Executive Vice
  President               1999    $212,625      --      --          100,000       $   476

- --------
(a) Includes employer's 401(k) plan contributions.
(b) Includes group term life insurance, automobile expense and parking
    expenses paid by employer, except for Mr. Gearon, in which case it
    includes group term life insurance only.
(c) Represents compensation paid by American Radio for 1997 and both American
    Radio and American Tower for 1998.

Option Grants in 1999

  The following table sets forth certain information relating to 1999 option
grants pursuant to the American Tower Systems Corporation 1997 Stock Option
Plan, as amended and restated (the "Stock Option Plan"), issued to the
individuals named in the Summary Compensation Table above.



                                                                          Potential Realizable
                                                                                Value at
                          Number of    Percent of                           Annual Rates of
                          Shares of  Total Options                            Appreciation
                          Underlying   Granted to   Exercise              for Option Terms(b)
                           Options    Employees in    Price   Expiration ----------------------
          Name             Granted   Fiscal Year(a) Per Share    Date        5%         10%
          ----            ---------- -------------- --------- ---------- ---------- -----------
                                                                  
Steven B. Dodge.........   300,000        5.56       $23.813   11/11/09  $4,492,666 $11,385,298
Douglas C. Wiest........    60,000        1.11       $23.813   11/11/09  $  898,533 $ 2,277,060
Joseph L. Winn..........    60,000        1.11       $23.813   11/11/09  $  898,533 $ 2,277,060
James S. Eisenstein.....    50,000         .93       $23.813   11/11/09  $  748,778 $ 1,897,550
J. Michael Gearon, Jr...   100,000        1.85       $23.813   11/11/09  $1,497,555 $ 3,795,099

- --------
(a) The total number of shares covered by options granted to employees and
    directors during 1999 pursuant to the Stock Option Plan was 5,391,450.
(b) A 5% and 10% per year appreciation in stock price from $23.813 per share
    yields appreciation of $14.97 per share and $37.95 per share,
    respectively. The actual value realized, if any, will depend on the excess
    of the stock price over the exercise price on the date the option is
    exercised, so that there is no assurance the value realized by an
    executive will be at or near the amounts reflected in this table.

                                      11


Aggregated Option Exercises in Last Fiscal Year and Fiscal Year-End Option
Values

  The following table sets forth certain information regarding the unexercised
options granted pursuant to the Stock Option Plan (or outstanding with respect
to options granted under the predecessors' plans) to the individuals referred
to in the Summary Compensation Table above. None of the individuals shown
exercised any options in 1999.



                                    Number of           Value of Unexercised
                             Unexercised Options at    In-the-Money Options at
                                December 31, 1999       December 31, 1999(a)
                            ------------------------- -------------------------
           Name             Exercisable Unexercisable Exercisable Unexercisable
           ----             ----------- ------------- ----------- -------------
                                                      
Steven B. Dodge............  1,325,066    3,176,191   $27,051,907  $46,531,319
Douglas C. Wiest...........     73,000      352,000   $ 1,013,330  $ 4,458,250
Joseph L. Winn(b)..........    255,177      641,232   $ 4,992,236  $ 9,235,925
James S. Eisenstein........    358,869      265,872   $ 8,724,499  $ 3,959,373
J. Michael Gearon, Jr. ....     66,891      367,560   $   959,773  $ 4,514,023

- --------
(a) Based on the closing price of the Class A Common Stock on the New York
    Stock Exchange (the "NYSE") on December 31, 1999 of $30.5625 per share.
(b) Mr. Winn exercised options for an aggregate of 203,709 shares of Class B
    Common Stock in 1998, realizing a value of $5,542,160 based on the closing
    price of the Company's Class A Common Stock on December 31, 1998 of $29.56
    per share.

Compensation Committee Report on Executive Compensation

  American Tower is a wireless communications and broadcast infrastructure
company, including a leading independent owner, operator and developer of
wireless communications and broadcast towers in the United States. The
Company's strategy is to use that position to take advantage of the growth
opportunities inherent in a rapidly expanding and highly fragmented
communications site industry. In order to implement this strategy and achieve
its goals, the Company believes that it is crucial to recruit, retain and
motivate imaginative and highly qualified management at the executive level.

  It is the Compensation Committee's responsibility to review, recommend and
approve the Company's compensation policies and programs, including all
compensation for the Chief Executive Officer and the other executive officers.
The Compensation Committee consists entirely of directors who are both "non-
employee" directors within the meaning of Rule 16b-3 under Section 16 of the
Securities Exchange Act of 1934, as amended (the "Exchange Act") and "outside"
directors within the meaning of Section 162(m) of the Internal Revenue Code of
1986, as amended (the "Code") and the regulations thereunder, so that grants
of options under the Stock Option Plan to executive officers are exempt under
Rule 16b-3 and eligible for the "performance-based" exception of Section
162(m) of the Code. The Compensation Committee administers the Stock Option
Plan and in exercise of that function determines what grants of stock options
thereunder are to be made to the Chief Executive Officer and the other
executive officers. The Compensation Committee also administers the American
Tower Corporation 1995 Stock Option Plan, the Specialty Teleconstructors, Inc.
1997 Stock Incentive Plan and the Specialty Teleconstructors, Inc. 1998 Stock
Option Plan, although no additional grants are to be made under those plans.

  The compensation policies adopted and implemented by the Compensation
Committee, combining base salary and incentive compensation principally in the
form of long-term stock options with a five-year vesting schedule, are
designed to achieve the operating and acquisition strategies and goals of the
Company. By placing a greater emphasis on the long-term incentive aspects of
the overall compensation program, it is hoped that financial incentives will
be provided to motivate those responsible for achieving those goals and, at
the same time, aligning the interests of those persons with the stockholders.
The purpose of the Stock Option Plan is to encourage key employees, directors
and advisors who render services of special importance to, and who have
contributed or are expected to contribute materially to the success of, the
Company to continue their association by providing favorable opportunities for
them to participate in stock ownership and in future growth. The Compensation
Committee made stock option grants to Messrs. Dodge, Eisenstein, Gearon,
Wiest, and Winn in 1999.

                                      12


  The Compensation Committee determined the salary levels of the executive
officers, including the Chief Executive Officer, for fiscal year 1999. The
compensation policies implemented by the Compensation Committee, which combine
base salary and incentive compensation in the form of long-term stock options,
are designed to achieve the operating and acquisition strategies and goals of
the Company. In particular, in determining salary levels for fiscal year 1999,
the Compensation Committee took into account the past or expected future
contributions of each executive officer to the Company's strategic goals,
especially the efforts of each such officer in connection with strategic
acquisitions, construction activities and sales and marketing activities.

  Section 162(m) of the Code generally disallows an income tax deduction to
public companies for compensation in excess of $1,000,000 paid in any year to
the chief executive officer or any of the four most highly compensated other
executive officers, to the extent that this compensation is not "performance-
based" within the meaning of Section 162(m). Although the Compensation
Committee has not adopted any specific rules with respect to this issue, its
general policy, subject to all then prevailing relevant circumstances, is to
attempt to structure compensation arrangements to maximize deductions for
federal income tax purposes.

                                          COMPENSATION COMMITTEE
                                          Thomas H. Stoner, Chairman
                                          Arnold L. Chavkin
                                          Maggie Wilderotter

Employment Agreements

  J. Michael Gearon, Jr. and Douglas C. Wiest are the only executive officers
who have employment agreements. Mr. Gearon entered into his employment
agreement in connection with the Gearon merger. That employment agreement is
for an initial term ending December 31, 2000 and is thereafter renewable for
successive one year periods. It provides that Mr. Gearon shall receive an
annual minimum base salary of $200,000 and shall be eligible to participate in
the Stock Option Plan and other benefits. Mr. Wiest's employment agreement
provides for a lump sum cash payment of $350,000, or 1.5 times his salary, if
Mr. Wiest's employment is terminated (except for cause) within five years of
the date of the employment agreement (April 13, 1998). It also provides that
under certain circumstances, if American Tower is sold within such five year
period, Mr. Wiest would be entitled to accelerated vesting of any options he
held at the time.

Compensation Committee Interlocks and Insider Participation

  The Chase Manhattan Bank ("Chase"), an entity related to CEA, CCP and Chase
Capital, affiliates of Mr. Chavkin, has been a lender to the Company and is a
lender under its credit facilities. See the explanation below under "Certain
Transactions."

Certain Transactions

  Chase was a lender in the Company's credit facilities with participation
ranging from 5.2% to 6.67% under the old credit facilities and a 6.6%
participation in certain of the Company's new credit facilities. Chase is an
affiliate of CCP, CEA and Chase Capital. CEA and Chase Capital are
stockholders of the Company. Mr. Chavkin, a director of American Tower, is a
general partner of CCP. The aggregate principal amount outstanding under the
credit facilities was $730.0 million as of March 1, 2000. Chase's share of
interest and fees paid by American Tower pursuant to its various credit
arrangements from January 1, 1999 to March 1, 2000 was $1.4 million.

  Mr. Eisenstein received a $1,022,366 demand loan in August 1998. As of March
1, 2000 the outstanding principal amount of the loan was $322,365, which was
the largest amount outstanding at any time since January 1, 1999.

                                      13


  Mr. Wiest received a $700,000 demand loan in March 1999 and an additional
advance in December 1999 of $100,000. As of March 1, 2000 the outstanding
principal amount of the loan was $800,000, which was the largest amount
outstanding at any time since January 1, 1999.

  Management believes that the above transactions, to the extent they were
with affiliated parties, were on terms, and American Tower intends to continue
its policy that all future transactions between it and its officers,
directors, principal stockholders and affiliates will be on terms, not less
favorable to the Company than those which could be obtained from unaffiliated
parties.

                                      14


Performance Graph

  The following graph compares the percentage change in the Class A Common
Stock to (1) the cumulative total return of the Russell Midcap Index (Broad
Market index), (2) the group of companies selected as the Company's peers in
the communications site industry in the 1999 Proxy Statement (the "Old Peer
Group"), and (3) the group of companies selected as the Company's peers in the
communications site industry at the current time (the "New Peer Group"),
assuming an investment of $100 on June 5, 1998. Commission rules require the
inclusion of both the Old Peer Group and the New Peer Group. The Old Peer
Group consists of the following companies: Crown Castle International Corp.,
Spectrasite Holdings Inc. (formerly Westower Corporation) and LCC
International, Inc. The New Peer Group includes all of the corporations in the
Old Peer Group as well as Pinnacle Holdings Inc. and SBA Communications
Corporation, both of which became public companies in 1999.

  On February 27, 1998, the Class A Common Stock commenced trading on a "when-
issued" basis on the inter-dealer bulletin board of the over-the-counter
market. The Class A Common Stock commenced trading on the NYSE on June 5, 1998
(the day after the ATC Separation). The following graph presents the trading
information commencing on June 5, 1998 and does not present the trading
information for such "when issued" market. The cumulative return assumes
reinvestment of all dividends. The performance of the Company's Class A Common
Stock reflected below is not necessarily indicative of future performance.

                     COMPARISON OF CUMULATIVE TOTAL RETURN
                      BETWEEN AMERICAN TOWER CORPORATION,
                  RUSSELL MIDCAP INDEX, AND PEER GROUP INDEX


                             [GRAPH APPEARS HERE]


                                6/5/98          9/98          12/98          3/99          6/99          9/99          12/99
                               ----------------------------------------------------------------------------------------------
                                                                                                
American Tower Corporation     $100.00        $111.48        $129.23        $107.10       $104.92       $85.79        $133.61
Russell Midcap Index            100.00          85.89          97.55          94.51        105.08        93.90          97.44
Old Group Index (a)             100.00          38.56          68.80          53.01         60.33        51.37          86.68
New Peer Group Index (a)        100.00          38.56          68.80          53.17         65.03        59.40          99.37


- --------
(a) The Company's 1999 Proxy Statement failed to accurately set forth the peer
    group performance data due to its failure to include market weighting of
    the component corporations. The data above accurately reflects market
    weighting and, therefore, differs substantially from the data presented in
    last year's proxy. In addition, although the data is presented on a
    quarterly basis, returns are adjusted on a monthly basis.

                                      15


                                    ITEM 2

         AMENDMENT OF THE COMPANY'S STOCK OPTION PLAN TO INCREASE THE
               NUMBER OF SHARES RESERVED FOR ISSUANCE THEREUNDER

  By resolutions adopted as of March 9, 2000, the Board of Directors approved,
and voted to recommend that the stockholders approve, an amendment to the
Stock Option Plan to increase the number of shares of Common Stock authorized
for issuance from 15,000,000 to 24,000,000.

  The Board of Directors believes that equity interests are an increasingly
significant factor in the ability to attract, retain and motivate the officers
and other key employees, directors and consultants that are critical to the
Company's long-term success. In approving the increase in the number of shares
reserved for issuance under the Stock Option Plan, the Board of Directors
considered several factors.

  One of the principal reasons underlying the proposal is the significant
increase in the scale of the operations that occurred during 1999. As a result
of the Company's acquisition strategy, it has hired a number of new employees
who were formerly employees of acquired companies or who were hired to replace
those employees or to perform functions directly resulting from expanded
operations. A significant number of options were granted to these new
employees.

  Another significant factor contributing to the need for additional shares in
the Stock Option Plan was the adoption of the policy, implemented in 1999,
that every employee receive an option to acquire at least 300 shares of Class
A Common Stock.

  Options for an aggregate of approximately 1,732,300 shares, representing
more than 32% of all shares underlying options granted since the 1999 Annual
Meeting, resulted from the growth in the number of employees and this new
policy.

  Finally, the Compensation Committee believed that the greatly expanded scope
of operations and responsibilities for corporate officers and other key
employees required the grant to those persons of additional options,
commensurate with those greater responsibilities, during 1999.

  The proposed total number of shares of 24,000,000 represents approximately
12% of the total number of shares of Common Stock that would be outstanding on
a pro forma basis, assuming conversion of all convertible notes and the
exercise of all options assumed under prior merger agreements and committed
under current merger agreements. The Board of Directors considered this number
as part of its deliberations in recommending the proposed increase.

  Because the employee option grants utilized the shares available under the
Stock Option Plan at a faster rate than anticipated at to the time of planning
the 1999 Annual Meeting when the stockholders approved the Stock Option Plan,
and because of the overall increase in the size of the Company and the number
of employees, the Company's stockholders are being asked to approve the
increase at the Annual Meeting.

  As of March 1, 2000, options for 14,366,846 shares of Common Stock had been
granted, and options for 14,015,751 shares were outstanding under the Stock
Option Plan at exercise prices ranging from $3.66 to $48.88 per share, and
633,154 shares were available for future grants. However, American Tower is
committed under existing merger agreements to issue options covering an
aggregate of 650,000 shares. If the amendment is approved, 9,633,154 shares of
Common Stock will be available for grants of options under the Stock Option
Plan. On March 22, 2000, the closing price per share of the Company's Class A
Common Stock, as reported in a summary of composite transactions in The Wall
Street Journal for stocks listed on the NYSE, was $53.00.

                                      16


Summary of the Stock Option Plan

  The following summary of the material features of the Stock Option Plan is
qualified in its entirety by reference to the full text of the Stock Option
Plan, which has been filed with the Commission and will be made available upon
request.

  Purpose, Participants, Effective Date and Duration. The Company instituted
the Stock Option Plan effective November 5, 1997 and amended and restated it
on April 27, 1998. The purpose of the Stock Option Plan is to encourage key
employees, directors and consultants of the Company and its Subsidiaries (a
Subsidiary is a corporation or other business organization the voting power or
equity interests of which are at least 50% owned by the Company, directly or
indirectly), who render services of special importance to the management,
operation or development of the Company or a Subsidiary, and who have
contributed or may be expected to contribute materially to the success of, the
Company or a Subsidiary (the "Participants"), to continue their association
with the Company and its Subsidiaries by providing favorable opportunities for
them to participate in the ownership of the Company and in its future growth
through the granting of options to acquire shares of the Class A Common Stock.
As of March 1, 2000, approximately 1,750 employees and seven non-employee
directors were eligible to participate in the Stock Option Plan. The Stock
Option Plan will terminate on November 15, 2007, unless earlier terminated by
the Board of Directors. Termination of the Stock Option Plan will not affect
awards made prior to termination, but awards may not be made after
termination.

  Shares Subject to the Stock Option Plan. The Stock Option Plan currently
provides that options may be granted to purchase shares of Class A Common
Stock. However, the Stock Option Plan currently limits the number of shares of
Common Stock for which options may be granted to an aggregate of 15,000,000
shares. These shares may be authorized and unissued shares or treasury shares.
The Stock Option Plan was amended in 1998 in connection with the Old ATC
merger as a result of which no options may now be granted to purchase Class B
Common Stock. In the event of any change in the number or kind of Class A and
Class B Common Stock outstanding pursuant to a reorganization, subdivision,
consolidation, recapitalization, exchange of shares, stock dividend or split
or combination of shares, appropriate adjustments will be made (1) to the
number of shares subject to outstanding options, (2) in the exercise price per
share of outstanding options, and (3) in the kind of shares which may be
issued under the Stock Option Plan. Shares will be deemed issued under the
Stock Option Plan only after full payment of the exercise price has been made.
To the extent that an award under the Stock Option Plan lapses or is
forfeited, any shares subject to such award will again become available for
grant under the terms of the Stock Option Plan. The Stock Option Plan provides
that American Tower may not grant options to purchase more than 5,000,000
shares per year to any individual.

  Administration. The Stock Option Plan is administered by the Compensation
Committee, which must consist solely of at least two directors who are both
"non-employee directors" within the meaning of Rule 16b-3 under the Exchange
Act and "outside directors" within the meaning of Section 162(m) of the Code.

  Subject to the terms of the Stock Option Plan, the Compensation Committee
has authority to: (1) select the persons to whom options shall be granted; (2)
determine the number or value and the terms and conditions of options granted
to each such person, including the price per share to be paid upon exercise of
any option and the period within which each such option may be exercised; and
(3) interpret the Stock Option Plan and prescribe rules and regulations for
the administration thereof.

  Stock Options. With regard to each option, the Compensation Committee
determines the number of shares subject to the option, the exercise price of
the option, the manner and time of exercise of the option and whether the
option is intended to qualify as an incentive stock option, or ISO, within the
meaning of Section 422 of the Code. Options that are not intended to qualify
as ISOs are referred to as nonqualified stock options, or NSOs. ISOs may only
be granted to employees of the Company. In the case of an ISO, the exercise
price may not be less than the "fair market value" of the shares on the date
the option is granted. However, in the case of an employee who owns (or is
considered to own under Section 424(d) of the Code) stock possessing more than
10% percent of the total combined voting power of all classes of stock of the
Company or any of its Subsidiaries,

                                      17


the price at which shares may be purchased pursuant to an ISO may not be less
than 110% of the fair market value of the class of Common Stock covered by the
option on the date the ISO is granted.

  The duration of the ISOs and NSOs granted under the Stock Option Plan are
required to be specified in a stock option agreement. However, no ISO may be
exercisable after the expiration of ten years after the date of grant and no
NSO may be exercisable after the expiration of ten years and one day after the
date of grant. In the case of any employee who owns (or is considered under
Section 424(d) of the Code as owning) stock possessing more than 10% of the
total combined voting power of all classes of stock of the Company or any of
its Subsidiaries, no ISO may be exercisable after the expiration of five years
from its date of grant. The Compensation Committee, in its discretion, may
provide that any option is exercisable during its entire duration or during
any lesser period of time.

  The option exercise price may be paid (1) in cash or a cash equivalent, (2)
through a so-called "cashless exercise" procedure, (3) to the extent permitted
by the Compensation Committee, in shares of Class A Common Stock owned by the
optionee or (4) to the extent permitted by the Compensation Committee, by
delivery of a recourse promissory note secured by, among other optionee
assets, the stock acquired upon exercise of the option. However, the optionee
may not make payment in shares that he acquired upon the earlier exercise of
any ISO, unless and until he has held the shares for at least two years after
the date the ISO was granted and at least one year after the date the ISO was
exercised.

  The following description of the federal income tax consequences of options
is general and does not purport to be complete.

  Tax Treatment of Options. An optionee realizes no taxable income when an NSO
is granted. Instead, the difference between the fair market value of the stock
subject to the NSO and the exercise price paid is taxed as ordinary
compensation income when the NSO is exercised. The difference is measured and
taxed as of the date of exercise, if the stock is not subject to a
"substantial risk of forfeiture", or as of the date or dates on which such
risk terminates in other cases. An optionee may elect to be taxed on the
difference between the exercise price and the fair market value of the stock
on the date of exercise, even though some or all of the stock acquired is
subject to a substantial risk of forfeiture. Gain on the subsequent sale of
the stock is taxed as capital gain. The Company receives no tax deduction on
the grant of an NSO, but is entitled to a tax deduction when the optionee
recognizes taxable income on or after exercise of the NSO, in the same amount
as the income recognized by the optionee.

  Generally, an optionee incurs no federal income tax liability on either the
grant or the exercise of an ISO, although an optionee will generally have
taxable income for alternative minimum tax purposes at the time of exercise
equal to the excess of the fair market value of the stock acquired over the
exercise price. Provided that the option stock is held for at least one year
after the date of exercise of the option and at least two years after its date
of grant, any gain realized on subsequent sale of the stock will be taxed as
long-term capital gain. If the stock is disposed of within a shorter period of
time, the optionee will recognize ordinary compensation income in an amount
equal to the lesser of his gain on the disposition or the difference between
the fair market value of the stock on the date of exercise of the option and
its fair market value on its date of grant. The Company receives no tax
deduction on the grant or exercise of an ISO, but is entitled to a tax
deduction if the optionee recognizes taxable income on account of a premature
disposition of ISO stock, in the same amount and at the same time as the
optionee's recognition of ordinary income.

  Amendments to the Stock Option Plan. The Board of Directors may modify,
revise or terminate the Stock Option Plan at any time and from time to time,
except that approval of a majority of the Company's stockholders is required
with respect to any amendment to change the number of shares that may be
issued under options in the aggregate or to any one employee, change the class
of persons eligible to receive options, reduce the exercise price of any ISO,
extend the latest date on which an ISO can be exercised, increase materially
the benefits accruing to any person under the Stock Option Plan, or make any
other change that requires stockholder approval under applicable law.

                                      18


Required Vote

  A majority of the votes properly cast by or on behalf of the holders of
Class A and Class B Common Stock at the Annual Meeting, voting as a single
class, is required to approve the amendment of the Stock Option Plan to
increase the number of shares of Common Stock issuable thereunder from
15,000,000 to 24,000,000.

  The Board of Directors recommends that the stockholders vote FOR the
approval of the amendment to the Stock Option Plan.

                                      19


                                    ITEM 3

        APPROVAL OF THE STOCK OPTION PLAN OF THE COMPANY'S WHOLLY-OWNED
                        SUBSIDIARY, ATC TELEPORTS, INC.

  The Boards of Directors of American Tower and its wholly-owned subsidiary,
ATC Teleports, Inc. ("Teleports"), unanimously approved the adoption of the
ATC Teleports, Inc. 1999 Stock Option Plan (the "Teleports Plan"), which
permits the issuance of options to purchase shares of common stock of
Teleports. For the reasons set forth below, the Board of Directors has
recommended to the stockholders that they approve the adoption of the
Teleports Plan.

  Although American Tower has the ability under the Stock Option Plan to award
options to purchase shares of Class A Common Stock to employees of
subsidiaries, the Company has determined that establishing a separate stock
option plan for Teleports employees will provide benefits beyond those that
could be achieved by offering options to purchase American Tower shares.
Specifically, Teleports is in a different line of business than American
Tower's principal business of owning and operating towers. The Boards of
Directors of both American Tower and Teleports believe that the ability to
award equity interests in Teleports' specific business is a significant factor
in its ability to attract, retain and motivate key employees, directors and
consultants that are critical to its long term success.

  In addition, under the Code, Teleports might not be entitled to certain
deductions attributable to exercises of options by certain persons unless the
Teleports Plan is approved by American Tower's stockholders. Specifically,
Section 162(m) of the Code disallows to a public company deductions for
compensation in excess of $1,000,000 paid to the chief executive officer or
any of the four most highly compensated other executive officers, unless an
exception applies. Executive officers of a subsidiary may constitute executive
officers of a parent company. One of the specified exceptions to the Section
162(m) limitation includes certain performance-based compensation, such as the
Teleports Plan, if it has been approved by the stockholders of the public
company. The Board of Directors of American Tower therefore recommends that
the stockholders vote in favor of the Teleports Plan.

Summary of the Teleports Plan

  The following summary of the material features of the Teleports Plan is
qualified in its entirety by reference to the full text of the Teleports Plan,
which has been filed with the Commission and will be made available upon
request. The Teleports Plan is substantially identical to the Stock Option
Plan. This summary sets forth only those provisions of the Teleports Plan that
differ materially from the Stock Option Plan. Refer to Item 2, above, for a
full discussion of the Stock Option Plan.

  Purpose, Participants, Effective Date and Duration. The Teleports Plan
provides for the issuance of options to officers, employees, directors and
consultants of Teleports and its "Affiliates." An Affiliate is a corporation
or other business organization which owns in Teleports, or in which Teleports
or any such corporation or business organization owns, directly or indirectly,
at least 50% of the total voting power of all classes of stock. The Teleports
Plan became effective as of November 10, 1999.

  Shares Subject to the Teleports Plan. The Teleports Plan currently limits
the number of shares of common stock of Teleports for which options may be
granted to an aggregate of 1,000,000 shares. The Teleports Plan provides that
it may not grant options to purchase more than 500,000 shares per year to any
individual.

  Administration. The Stock Option Plan is administered by the compensation
committee of Teleports (the "Teleports Committee"). Currently, the Teleports
Committee is not comprised of two "outside directors" within the meaning of
Section 162(m) of the Code. The Teleports Plan provides that under these
circumstances the compensation committee of American Tower must grant options
under the Teleports Plan. Rule 16b-3 under the Exchange Act does not currently
apply.

  Stock Options. The Teleports Committee may, in its sole discretion,
accelerate options upon such terms and conditions as the Teleports Committee
may determine.

                                      20


  Certain Rights of Teleports. Shares of stock acquired pursuant to the
exercise of an option may not be transferred without the consent of the
Teleports Committee, which consent may be withheld or conditioned as it may
determine in its sole discretion. In the event of an involuntary transfer,
such as one resulting from divorce or death, then Teleports has the right to
repurchase such shares no earlier than 180 days after the exercise of the
option and no later than 365 days following the later of (a) the date of such
involuntary transfer and (b) the Teleports Committee's receipt of written
notice of the occurrence of such event. Similarly, if an optionee's employment
with Teleports or an Affiliate shall terminate for any reason, whether with or
without "cause" (as defined below), including retirement, then Teleports shall
have the right to repurchase such shares no later than 365 days following the
date of the optionee's termination.

  In the event of an involuntary transfer or termination other than for
"cause," the repurchase price shall be the fair market value of the stock. In
the event of a termination for "cause," the repurchase price shall be the
lesser of (1) the fair market value of the stock or (2) the exercise price.
"Cause" is defined as a determination by the Teleports Committee that the
optionee has engaged in fraud, embezzlement, theft, commission of a felony or
dishonesty in the course of his or her employment by, or involvement with,
Teleports or an Affiliate. "Cause" may also include the failure of the
optionee to perform his or her duties diligently, or the material breach of
the optionee of any rules of conduct, policies or regulations of Teleports or
an Affiliate.

  In addition, the Teleports Committee may require the optionee, as
appropriate, to enter into any applicable stockholder or noncompetition
agreement.

  Amendments to the Teleports Plan. The Teleports Committee may, without
obtaining stockholder approval, increase materially the benefit accruing to
any person under the Teleports Plan.

Required Vote

  A majority of the votes properly cast by or on behalf of the holders of
Class A and Class B Common Stock at the Annual Meeting, voting as a single
class, is required to approve the Teleports Plan.

  The Board of Directors recommends that the stockholders vote FOR the
approval of the Teleports Plan.

                                      21


                                    ITEM 4

       APPROVAL OF THE STOCK OPTION PLAN OF KLINE IRON & STEEL CO., INC.

  The Board of Directors of American Tower unanimously approved the adoption
of the Kline Iron & Steel Co., Inc. ("Kline") 2000 Stock Option Plan (the
"Kline Plan"), subject to consummation of the merger described below. For the
same reasons set forth above for the Teleports Plan, the Board of Directors
has recommended to the stockholders that they approve the adoption of the
Kline Plan. At the present time, American Tower owns 33.33% of Kline. On
December 29, 1999, Kline and American Tower entered into letter of intent for
the acquisition of Kline by the Company. The transaction is structured as a
merger. Upon consummation of the merger, Kline will become a wholly-owned
subsidiary of American Tower. Subject to satisfaction of customary closing
conditions, the merger is expected to occur at the end of March, 2000. If the
merger has not yet occurred, approval of the Kline Plan will be conditioned on
consummation of the merger with Kline.

  Like the Teleports Plan, the Kline Plan covers common stock of Kline, not
American Tower. The Boards of Directors of both American Tower and Kline
believe that the ability to award equity interests in Kline's specific
business is a significant factor in its ability to attract, retain and
motivate key employees, directors and advisors that are critical to its long
term success.

  For the same reasons as stated above with respect the Teleports Plan, the
stockholders are being asked to approve the Kline Plan.

Summary of the Kline Plan

  The following summary of the material features of the Kline Plan is
qualified in its entirety by reference to the full text of the Kline Plan,
which has been filed with the Commission and will be made available upon
request. The Kline Plan is substantially identical to the Teleports Plan. This
summary sets forth only those provisions of the Kline Plan that differ
materially from the Teleports Plan. Refer to Items 2 and 3, above, for a full
discussion of the American Tower Stock Option Plan and the Teleports Plan.

  Purpose, Participants, Effective Date and Duration. The Kline Plan will be
effective as of the date the merger is consummated.

  Shares Subject to the Kline Plan. The Kline Plan currently limits the number
of shares of common stock of Kline for which options may be granted to an
aggregate of 500,000 shares. The Kline Plan provides that it may not grant
options to purchase more than 100,000 shares per year to any individual.

Required Vote

  A majority of the votes properly cast by or on behalf of the holders of
Class A and Class B Common Stock at the Annual Meeting, voting as a single
class, is required to approve the Kline Plan.

  The Board of Directors recommends that the stockholders vote FOR the
approval of the Kline Plan.

                                      22


                                    ITEM 5

                  ADOPTION OF THE AMERICAN TOWER CORPORATION
                       2000 EMPLOYEE STOCK PURCHASE PLAN

  On March 9, 2000 the Board of Directors approved, and is proposing for
stockholder approval, the adoption of the American Tower Corporation 2000
Employee Stock Purchase Plan (the "2000 Employee Stock Purchase Plan"). The
purpose of the 2000 Employee Stock Purchase Plan is to provide employees of
the Company and its Subsidiaries the opportunity to acquire a proprietary
interest in the Company by providing favorable terms for them to purchase its
stock.

  The Board of Directors believes that the availability of equity interests is
significant in the Company's ability to attract, retain and motivate employees
who are critical to the Company's long-term success, and that the adoption of
the 2000 Employee Stock Purchase Plan will further the goal of providing
employees with incentives to serve the Company.

2000 Employee Stock Purchase Plan

  The following is a summary of the 2000 Employee Stock Purchase Plan and is
subject to and qualified in its entirety by reference to the complete text of
the 2000 Employee Stock Purchase Plan, which has been filed with the
Commission and will be made available upon request.

  Overview. The total amount of Class A Common Stock with respect to which the
right to purchase Class A Common Stock may be granted under the 2000 Employee
Stock Purchase Plan will not exceed in the aggregate 5,000,000 shares. If an
option granted under the 2000 Employee Stock Purchase Plan expires or is
surrendered or cancelled, the shares allocable to the option will again be
available under the plan.

  Commencing July 1, 2000, eligible employees will be able to set aside
payroll deductions to exercise options to purchase Class A Common Stock under
the 2000 Employee Stock Purchase Plan. If the plan is approved by the
stockholders, options under the 2000 Employee Stock Purchase Plan will be
granted in a series of offerings of Class A Common Stock (each an "Offering").
The Compensation Committee will determine the date of the first and subsequent
Offerings (the "Offering Date") and the end of each Offering (the "Exercise
Date"). Options will be exercised on the Exercise Date. There will be at least
one Offering in any consecutive twelve-month period, and the Exercise Date
with respect to an Offering shall be not more than twelve months after the
Offering Date. Offerings will continue until all of the shares of Class A
Common Stock available under the 2000 Employee Stock Purchase Plan have been
exhausted, or until the 2000 Employee Stock Purchase Plan has been terminated
by the Board of Directors or has terminated by its terms. Payroll deductions
accumulated during the Offering will be used to pay the "Option Price." Each
participant will purchase the number of whole shares of Class A Common Stock
equal to the payroll deductions accumulated during the Offering divided by the
Option Price. If insufficient shares are available, a pro rata allocation of
remaining shares will be made. The "Option Price" of shares of Class A Common
Stock will be the lesser of: (1) 85% of the fair market value of the shares on
the Offering Date or (2) 85% of the fair market value of the shares on the
Exercise Date. Fair market value will generally be the mean between the
highest and lowest sale price of the stock on the date in question. In no
event will a participant be granted an option to acquire more than the number
of whole shares of Class A Common Stock equal to $25,000 divided by the fair
market value of the shares as of the Offering Date.

  Eligibility and Participation. Any employee of the Company or any Subsidiary
who has been employed for at least 90 days may participate in any Offering
under the 2000 Employee Stock Purchase Plan by completing an authorization for
after-tax payroll deductions in connection with the Offering prior to the
Offering Date. A participant may authorize payroll deductions from one to
fifteen percent of his or her compensation on each pay day. A participant can
decrease his or her rate of deductions and can withdraw entirely from an
Offering, but he or she can never increase the rate of payroll deductions once
an Offering begins.

                                      23


  The following employees are ineligible to participate: (1) any employee who
is a member of a collective bargaining unit that has elected not to
participate in the 2000 Employee Stock Purchase Plan, (2) any employee of a
Subsidiary none of the employees of which participate in the 2000 Employee
Stock Purchase Plan, as determined by the Compensation Committee and (3) any
employee who owns, directly or indirectly, as of an Offering Date five percent
or more of the total combined voting power or value of all classes of capital
stock of the Company or of any Subsidiary. In addition, no employee will be
granted an option that would cause him or her to own (or be considered to own)
or hold outstanding options to purchase five percent or more of the total
combined voting power or value of all classes of capital stock of the Company
or any Subsidiary or that permits his or her right to purchase shares under
all employee stock purchase plans of the Company and its Subsidiaries to
accrue at a rate that exceeds $25,000 for any calendar year.

  Administration. The 2000 Employee Stock Purchase Plan, which is effective
July 1, 2000, may be administered by the Board of Directors or, in its
discretion, by a committee composed of at least two individuals who may be
members of the Board of Directors or employees of the Company. The Board of
Directors has determined that if the 2000 Employee Stock Purchase Plan is
approved by the stockholders, it will initially be administered by the
Compensation Committee. The Compensation Committee shall have the authority to
adopt, amend and rescind such rules and regulations as, in its opinion, may be
advisable in the administration of the 2000 Employee Stock Purchase Plan and
to decide all questions of interpretation and application of such rules and
regulations, which decision is final and binding. The Compensation Committee
has the authority to change the Offering Date and the Exercise Date, as well
as the authority to increase the number of Offerings each year.

  Withdrawal. A participant may, at such time prior to Exercise Date and in
such manner as the Compensation Committee may prescribe, withdraw from an
Offering and receive cash equal to the amount of the participant's accumulated
payroll deductions under the 2000 Employee Stock Purchase Plan. In no event
will a participant receive interest with respect to payroll deductions,
whether used to purchase Class A Common Stock or returned in cash.

  Termination of Employment. Options are nontransferable by a participant, and
no amount accumulated by a participant may be assigned, transferred, pledged
or otherwise disposed of in any way by a participant. Upon termination of a
participant's employment with the Company or a Subsidiary for any reason other
than death, an amount in cash equal to the participant's accumulated payroll
deductions under the 2000 Employee Stock Purchase Plan will be paid to the
participant. If a participant dies prior to the Exercise Date, the executor,
the administrator or a personal representative of the estate may request that
the balance of the participant's accumulated payroll deductions be used to
exercise the option granted prior to the participant's death. Any such
election must be made not later than the Exercise Date.

  Forfeiture for Dishonesty. If the Board of Directors determines that a
participant has engaged in fraud, embezzlement, theft, commission of a felony
or dishonesty in the course of his or her employment that has damaged the
Company or a Subsidiary or has disclosed trade secrets or other proprietary
information of the Company or a Subsidiary (a) the individual's participation
in an Offering will terminate and he or she will forfeit his or her right to
receive any Class A Common Stock pursuant to an Offering that has not yet been
delivered and (b) the Company will have the right to repurchase all or any
part of the shares of Class A Common Stock acquired by the participant upon
the earlier exercise of any option, at a price equal to the amount paid to the
Company upon exercise, together with interest.

  Change in Capital Structure. If there is a change in the capital structure
of the Company, by reason of a reorganization, recapitalization, exchange of
shares, stock split, combination of shares or dividend payable in shares or
other securities, a corresponding adjustment will be made by the Compensation
Committee in the number and kind of shares or other securities covered by
outstanding options and for which options may be granted under the 2000
Employee Stock Purchase Plan, and in the Option Price. If while unexercised
options remain outstanding under the 2000 Employee Stock Purchase Plan the
Company merges or consolidates with a wholly owned subsidiary for purposes of
reincorporating itself under the laws of another jurisdiction, the
participants will be entitled to acquire shares of common stock of the
reincorporated company upon the same

                                      24


terms and conditions as were in effect immediately prior to such
reincorporation. If while unexercised options remain outstanding under the
2000 Employee Stock Purchase Plan the Company merges or consolidates with one
or more corporations (whether or not the Company is the surviving
corporation), or is liquidated or sells or otherwise disposes of substantially
all of its assets to another entity, then the Compensation Committee, in its
discretion, will provide that either: (1) after the effective date of the
merger, consolidation, liquidation or sale, each participant is entitled, upon
exercise of an option, to receive in lieu of shares of Class A Common Stock
the number and class of shares of such stock or other securities to which he
or she would have been entitled pursuant to the terms of the merger,
consolidation, liquidation or sale, if he or she had been the holder of record
of the number of shares of Class A Common Stock as to which the option is
being exercised or (2) all outstanding options must be exercised as of the day
preceding the merger, consolidation, liquidation or sale, except that each
participant will be notified of his or her right to withdraw from the Offering
and receive a refund of his or her payroll deductions.

  Amendment or Termination of 2000 Employee Stock Purchase Plan. The Board of
Directors may at any time terminate or amend, modify or suspend the 2000
Employee Stock Purchase Plan, provided that without stockholder approval there
shall be no: (1) change in the number of shares of Class A Common Stock that
may be issued under the 2000 Employee Stock Purchase Plan, except in the event
of a change in capital structure of the Company; (2) change in the class of
persons eligible to participate in the 2000 Employee Stock Purchase Plan; or
(3) other change in the 2000 Employee Stock Purchase Plan that requires
stockholder approval under applicable law. No amendment will adversely affect
outstanding options without the consent of the participant, and the
termination of the 2000 Employee Stock Purchase Plan will not terminate
options then outstanding, without the consent of the participant.
Notwithstanding the preceding sentence, the Board of Directors has the power
to make any changes to the 2000 Employee Stock Purchase Plan that may, in the
opinion of counsel for the Company, be necessary or appropriate from time to
time to enable it to qualify as an employee stock purchase plan under Section
423 of the Code and for any option granted thereunder to receive preferential
federal income tax treatment. In the event the Company is no longer publicly
held, the Company, at its option, may terminate the 2000 Employee Stock
Purchase Plan and, upon the termination, outstanding options will be cancelled
and each participant will receive in cash an amount equal to his or her
accumulated payroll deductions immediately prior to termination. Unless the
2000 Employee Stock Purchase Plan is terminated earlier, it will terminate on
the business date as of which there are no longer any shares available to be
offered.

  The following description of the federal income tax consequences of the 2000
Employee Stock Purchase Plan is general and does not purport to be complete.
In addition, the description does not discuss the tax consequences arising as
a result of the participant's death or under the laws of any state or foreign
country in which the participant may reside.

  Federal Income Tax Consequences of the 2000 Employee Stock Purchase
Plan. The 2000 Employee Stock Purchase Plan is intended to constitute an
employee stock purchase plan under Section 423 of the Code. As presently in
effect, under Section 423 of the Code, a participant will not realize income
as a result of either the grant of an option to acquire Class A Common Stock
as of an Offering Date or the acquisition of Class A Common Stock by exercise
of the option as of the Exercise Date. If the participant does not dispose of
the Class A Common Stock before the earlier of two years after the Offering
Date or one year after the Exercise Date, then upon the subsequent sale of the
Class A Common Stock, he or she will have ordinary compensation income of the
lesser of 15% of the fair market value of the Class A Common Stock as of the
Offering Date or the excess, if any, of the selling price of the Class A
Common Stock over the Option Price. Any additional gain or loss will be
treated as long-term capital gain or loss. The Company is not entitled to an
income tax deduction with respect to the ordinary compensation income
described above. If the participant disposes of the stock before the earlier
of two years after the Offering Date or one year after the Exercise Date, then
the excess, if any, of the fair market value of the Class A Common Stock on
the Exercise Date over the Option Price will be ordinary compensation income
to the participant, and the Company will be entitled to a deduction with
respect to that income. Any additional gain or loss will be treated as short-
term or long-term capital gain or loss, depending on the holding period.

                                      25


Required Vote

  A majority of the votes properly cast by or on behalf of the holders of
Class A and Class B Common Stock at the Annual Meeting, voting as a single
class, is required to approve the 2000 Employee Stock Purchase Plan.

  The Board of Directors recommends that the stockholders vote FOR the
proposal to adopt the 2000 Employee Stock Purchase Plan.

                                    ITEM 6

               RATIFICATION OF SELECTION OF INDEPENDENT AUDITORS

  Subject to ratification by the stockholders, the Board of Directors has
selected the firm of Deloitte & Touche LLP as the Company's independent
auditors for the current year. Deloitte & Touche LLP has served as the
Company's independent auditors since its organization.

  Representatives of Deloitte & Touche LLP are expected to be present at the
Annual Meeting. They will have the opportunity to make a statement if they
desire to do so and will also be available to respond to appropriate questions
from stockholders.

  If the stockholders do not ratify the selection of Deloitte & Touche LLP as
the Company's independent auditors, the selection of such auditors will be
reconsidered by the Board of Directors.

Required Vote

  A majority of the votes properly cast by or on behalf of the holders of
Class A and Class B Common Stock at the Annual Meeting, voting as a single
class, is required to approve the selection of Deloitte & Touche LLP as the
Company's independent auditors for 2000.

  The Board of Directors recommends that the stockholders vote FOR the
ratification of the selection of Deloitte & Touche LLP to serve as the
Company's independent auditors for the current fiscal year.

                                      26


                            ADDITIONAL INFORMATION

Other Matters

  The Board of Directors does not know of any other matters that may come
before the Annual Meeting. However, if any other matters are properly
presented at the meeting, it is the intention of the persons named in the
accompanying proxy or their substitutes acting hereunder, to vote, or
otherwise act, in accordance with their best judgment on such matters.

Section 16(a) Beneficial Ownership Reporting Compliance

  Section 16(a) of the Exchange Act requires the Company's directors,
executive officers and persons who own more than ten percent of a registered
class of the Company's equity securities to file reports of ownership on Form
3 and changes in ownership on Form 4 or 5 with the Commission. Such officers,
directors and ten-percent stockholders are also required by SEC rules to
furnish the Company with copies of all Section 16(a) reports they file. Based
solely on its review of the copies of such forms received by it, or written
representation from certain reporting persons that they were not required to
file a Form 5, the Company believes that, during the fiscal year ended
December 31, 1999, its officers, directors and ten-percent stockholders
complied with all Section 16(a) filing requirements applicable to such
individuals, except: (1) the purchase of 2,000 shares of Class A Common Stock
by Mr. Dodge's wife in July, 1998 was not reported until March 10, 2000, (2)
Mr. Michael Gearon did not report a sale of 69,500 shares of Class A Common
Stock in August, 1999 until February, 2000, and (3) Mr. Jack Furst has not
reported options granted in November, 1999 that are deemed to be beneficially
owned by him.

Proposals of Stockholders

  A stockholder who intends to present a proposal at the 2001 Annual Meeting
of Stockholders for inclusion in the Company's 2001 proxy statement and proxy
card relating to that meeting must submit such proposal by December 1, 2000.
In order for the proposal to be included in the proxy statement, the
stockholder submitting the proposal must meet certain eligibility standards
and comply with certain procedures established by the Commission, and the
proposal must comply with the requirements as to form and substance
established by applicable laws and regulations. Commission rules set forth
standards as to what stockholder proposals are required to be included in a
proxy statement for an annual meeting.

  For a proposal of a stockholder (including director nominations) to be
presented at the Company's 2001 Annual Meeting of Stockholders, other than a
stockholder proposal to be included in the Company's 2001 proxy statement as
discussed in the preceding paragraph, a stockholder's notice must be received
by American Tower at its principal executive offices by February 14, 2001. The
notice must include a brief description of the proposal, the reasons for such
proposal, any material interest in such proposal by the shareholder, the name
and address of the stockholder as it appears on the Company's books and the
class and number of shares of the Company beneficially owned by the
stockholder.

  All proposals and notices must be mailed to the Company's principal
executive office, at the address stated herein, and should be directed to the
attention of the General Counsel.

FORM 10-K

  A copy of the Company's Annual Report on Form 10-K for the fiscal year ended
December 31, 1999 as filed with the Commission, except for exhibits, will be
furnished without charge to any stockholder upon written request to Ms. Anne
Alter, Director of Investor Relations, American Tower Corporation, 116
Huntington Avenue, Boston, Massachusetts 02116.

                                          By Order of the Board of Directors,



                                          /s/ Steven B. Dodge
                                          Steven B. Dodge
                                          Chairman of the Board, President and
                                          Chief Executive Officer

March 27, 2000

                                      27


                                                                         ANNEX A


                           AMERICAN TOWER CORPORATION

                       2000 EMPLOYEE STOCK PURCHASE PLAN

1.  PURPOSE

     The purpose of this 2000 Employee Stock Purchase Plan (the "Plan") is to
provide employees of American Tower Corporation (the "Company") and its
Subsidiaries the opportunity to acquire a proprietary interest in the Company by
providing favorable terms for them to purchase its stock.  This Plan is intended
to qualify as an employee stock purchase plan within the meaning of Section 423
of the Code.

2.  DEFINITIONS

(a)   "Board" shall mean the Board of Directors of the Company.

(b)   "Code" shall mean the Internal Revenue Code of 1986, as amended.  Any
reference to a particular Section shall include any successor and regulation
thereto.

(c)   "Committee" shall have the meaning set forth in Section 3.

(d)   "Common Stock" shall mean the shares of the Company's Class A Common
Stock, $0.01 par value per share.

(e)   "Compensation" shall mean the amount reported (or to be reported) in Box 1
of Form W-2, or its equivalent, increased by any salary reduction elected
pursuant to Sections 402(g), 1321(f) or 125 of the Code.

(f)   "Employee" shall mean any individual who has been employed at least 90
days by the Company or any Subsidiary. The term Employee shall not include: (i)
any individual who is not a common law employee of the Company or a Subsidiary;
(ii) any Employee who owns, directly or indirectly, as of the Offering Date five
percent or more of the total combined voting power or value of all class of
stock of the Company or a Subsidiary; (iii) any individual who is a common law
employee of a Subsidiary, none of the employees of which participate in the
Plan, as determined by the Committee; and (iv) any Employee who is a member of
a collective bargaining unit with which the Company or a Subsidiary has
bargained in good faith with respect to participation in the Plan and as a
result of such bargaining the labor organization made an affirmative decision
not to participate in the Plan.

(g)   "Exchange Act" shall mean the Securities Exchange Act of 1934, as amended.

(h)   "Exercise Date" shall mean the date(s) designated by the Committee from
time to time on which an Optionee may exercise an Option; provided, however,
that no Exercise Date shall be more than 12 months after the applicable Offering
Date; and provided, further, that if such date is not a business day, the
Exercise Date shall be the business day immediately preceding the applicable
date.


(i)   "Fair Market Value" shall be determined according to the following rules:
(i) if the Common Stock is not at the time listed or admitted to trading on a
stock exchange or the Nasdaq National Market, the fair market value shall be the
closing price of the Common Stock on the date in question in the over-the-
counter market, as such price is reported in a publication of general
circulation selected by the Board and regularly reporting the price of the
Common Stock in such market; provided, however, that if the price of the Common
Stock is not so reported, the fair market value shall be determined in good
faith by the Board, which may take into consideration (1) the price paid for the
Common Stock in the most recent trade of a substantial number of shares known to
the Board to have occurred at arm's length between willing and knowledgeable
investors, or (2) an appraisal by an independent party, or (3) any other method
of valuation undertaken in good faith by the Board, or some or all of the above
as the Board shall in its discretion elect; or (ii) if the Common Stock is at
the time listed or admitted to trading on any stock exchange or the Nasdaq
National Market, then the fair market value shall be the mean between the lowest
and highest reported sale prices (or the lowest reported bid price and the
highest reported asked price) of the Common Stock on the date in question on the
principal exchange on which the Common Stock is then listed or admitted to
trading. If no reported sale of Common Stock takes place on the date in question
on the principal exchange or the Nasdaq National Market, as the case may be,
then the reported closing sale price (or the reported closing asked price) of
the Common Stock on the prior trading date immediately preceding such date on
the principal exchange or the Nasdaq National Market, as the case may be, shall
be determinative of fair market value.

(j)   "Insider" shall mean a person subject to Section 16 of the Exchange Act.

(k)   "Offering" shall mean any offering of Common Stock in accordance with
Section 7.

(l)   "Offering Date" shall mean the date(s) designated by the Committee from
time to time on which an Option is granted; provided, however, that there shall
be at least one Offering Date in any consecutive 12-month period while the Plan
remains in effect; and provided, further, that if such date is not a business
day, the Offering Date shall be the business day immediately preceding the
applicable date.

(m)   "Option" shall mean the right of a Participant to purchase Common Stock
pursuant to an Offering.

(n)   "Option Price" shall have the meaning set forth in Section 8.

(o)   "Optionee" shall mean any individual who has been granted an Option that
remains outstanding under the terms of any Offering or who owns Common Stock as
a result of an Offering.

(p)   "Participant" shall mean an Employee who has in effect a payroll deduction
authorization in accordance with Section 6.

(q)   "Securities Act" shall mean the Securities Act of 1933, as amended.

(r)   "Subsidiary" shall mean a corporation of which the Company owns, directly
or indirectly through an unbroken chain of ownership, fifty percent or more of
the total combined voting power of all classes of stock, whether or not such
corporation now exists or is hereafter organized or acquired by the Company or a
Subsidiary.

                                     - 2 -


3.  ADMINISTRATION OF THE PLAN

     The Plan shall be administered by the Board or, in the discretion of the
Board, a committee composed of at least two individuals who may be members of
the Board or employees of the Company or a Subsidiary (the "Committee").  In the
event that a vacancy on the Committee occurs on account of the resignation of a
member or the removal of a member by vote of the Board, a successor member shall
be appointed by vote of the Board.  No member of the Committee shall be liable
for any action or determination made in good faith with respect to the Plan.
All references in the Plan to the "Committee" shall be understood to refer to
the Committee or the Board, whoever shall administer the Plan.

     The Committee shall select one of its members as Chairman and shall hold
meetings at such times and places as it may determine.  A majority of the
Committee shall constitute a quorum, and acts of the Committee at which a quorum
is present, or acts reduced to or approved in writing by all the members of the
Committee, shall be the valid acts of the Committee.  The Committee shall have
the authority to adopt, amend and rescind such rules and regulations as, in its
opinion, may be advisable in the administration of the Plan.  All questions of
interpretation and application of such rules and regulations, of the Plan and of
Options granted thereunder shall be subject to the determination of the
Committee, which shall be final and binding.

     The Committee shall have the authority, without the need for further
approval, to establish a different Offering Date and/or Exercise Date, to modify
the amount of time between an Offering Date and an Exercise Date and to increase
or decrease the number of Offerings in a year.

     With respect to Insiders, transactions under the Plan are intended to
comply with all applicable conditions of Rule 16b-3 or its successor under the
Exchange Act.  To the extent any provision of the Plan or action by the
Committee fails to so comply, it shall be deemed to be modified so as to be in
compliance with such Rule or, if such modification is not possible, it shall be
deemed to be null and void, to the extent permitted by law and deemed advisable
by the Committee.

4.  OPTION SHARES

     The total amount of Common Stock with respect to which Options may be
granted under the Plan shall not exceed in the aggregate 5,000,000 shares from
either authorized but unissued shares or treasury shares; provided, however,
that such aggregate number of shares shall be subject to adjustment in
accordance with Section 15.  If any outstanding Option expires for any reason,
including a withdrawal pursuant to Section 10, or terminates by reason of the
severance of employment of the Participant or any other cause, or is
surrendered, the shares of Common Stock allocable to the unexercised portion of
the Option may again be made subject to an Option under the Plan.

5.  ELIGIBILITY

     An Employee shall be eligible to become a Participant in the Plan on any
Offering Date on which the Employee is employed by the Company or a Subsidiary;
provided, however, that no Employee shall be granted an Option:

                                     - 3 -


      (i)  if immediately after the grant the aggregate amount of stock the
   Employee would be considered to own under Section 424(d) of the Code,
   including stock that may be purchased with outstanding options, would
   represent five percent or more of the total combined voting power or value of
   all classes of capital stock of the Company or of any Subsidiary; or

      (ii) that permits the Employee's right to purchase shares under all
   employee stock purchase plans (within the meaning of Section 423 of the Code)
   of the Company and its Subsidiaries to accrue at a rate that exceeds $25,000
   for any calendar year, determined by reference to the Fair Market Value of
   the shares at the time any option is granted.

6.  PARTICIPATION

   (a) An Employee may become a Participant in any Offering by completing an
authorization for payroll deductions in connection with the Offering at such
time (prior to the Offering Date) and in such manner as the Committee may
prescribe. Payroll deductions pursuant to an authorization shall commence with
the payroll period in which the Offering Date occurs and shall end with the last
payroll completed prior to the Exercise Date for the Offering to which the
authorization applies, unless the authorization is sooner terminated by the
Participant as provided in Section 10. The Committee may provide that in the
case of the first Offering, payroll deductions shall commence with the first
payroll period ending after the initial Offering Date. All payroll deductions
shall be made on an after-tax basis.

    (b) A Participant shall elect in the authorization for payroll deduction to
have deductions made from his or her Compensation on each payday in an amount
equal to a whole percentage of from one to fifteen percent of his Compensation.
All payroll deductions made for a Participant shall be credited to a bookkeeping
account maintained for such Participant under the Plan. In no event shall
interest be paid to a Participant with respect to payroll deductions credited to
the Participant's account, whether such deductions are used in connection with
the exercise of an Option or are returned to the Participant or the
Participant's estate in cash.

    (c)  Except as may be required by law, a Participant may not make any
payments to the Participant's account other than by authorization for payroll
deduction. A Participant may elect to decrease the payroll deduction rate at
such time and in such manner as the Committee may prescribe. In no event shall a
Participant increase the amount of payroll deductions during an Offering. A
Participant may discontinue participation in the Offering as provided in Section
10.

7.  GRANT OF OPTIONS

    (a)  Options under the Plan shall be granted in a series of Offerings, the
first of which shall begin on the first Offering Date designated by the
Committee. Successive Offerings shall begin on each Offering Date thereafter
until all of the shares of Common Stock available under the Plan are exhausted
or until the Plan is terminated pursuant to Section 18 or Section 19.
Participation by an Employee in any Offering shall neither limit nor require his
participation in any other Offering.

    (b)  Each Participant in an Offering shall be granted, as of the applicable
Offering Date, an Option to purchase that number of whole shares of Common Stock
that the accumulated payroll deductions credited to his account during the
Offering is able to purchase at the Option Price.

                                     - 4 -


    (c)  If the total number of shares for which Options are to be granted as of
any Offering Date exceeds the number of shares then available under the Plan,
the Committee shall make a pro rata allocation of the available shares in a
manner as nearly uniform as practicable, and as it shall determine to be
equitable. In that event, the payroll deductions made or to be made pursuant to
authorizations for that Offering shall be reduced accordingly, and the Committee
shall give written notice of such reduction to each affected Participant.

    (d)  In no event shall a Participant be granted an Option in any Offering to
acquire more than that number of whole shares of Common Stock equal to $25,000
divided by the Fair Market Value of the shares as of the Offering Date;
provided, however, that such limit shall be subject to Section 5(ii) and to the
adjustment in accordance with Section 15.

8.  OPTION PRICE

     The Option Price of shares of Common Stock for any Offering shall be the
lesser of: (a) 85 percent of the Fair Market Value of the shares on the Offering
Date; or (b) 85 percent of the Fair Market Value of the shares on the Exercise
Date.

9.  EXERCISE OF OPTIONS

    (a)  A Participant's Option for an Offering will be exercised automatically
as of the Exercise Date for the Offering to purchase that number of whole shares
of Common Stock equal to the accumulated payroll deductions credited to the
Participant's account as of the Exercise Date divided by the Option Price.

    (b)  As promptly as practicable after each Exercise Date the Company shall
deliver to each Participant in the Offering, in accordance with the
Participant's election, either (a) the shares purchased upon the exercise of the
Participant's Option, together with a cash payment equal to the balance of any
payroll deductions credited to the Participant's account during the Offering
that were not used for the purchase of shares, other than amounts representing
fractional shares, or (b) a cash payment equal to the total of the payroll
deductions credited to the Participant's account during the Offering. Amounts
representing fractional shares will, at the discretion of the Committee, either
be carried forward for use in the next Offering if the Participant will
participate in that Offering or paid to the Participant in cash.

    (c)  The shares purchased upon exercise of an Option shall be deemed to be
transferred to the Participant on the Exercise Date.

10.  WITHDRAWAL FROM OFFERING

     A Participant may at any time prior to the Exercise Date at such time and
in such manner as the Committee may prescribe withdraw from an Offering and
request payment of an amount in cash equal to the accumulated payroll deductions
credited to the Participant's account under the Plan.  Such amount will be paid
to the Participant as promptly as practicable after receipt of

                                     - 5 -


the Participant's request to withdraw, and no further payroll deductions will be
made from the Participant's Compensation with respect to the Offering then in
progress and any outstanding Option shall be cancelled. A Participant's
withdrawal from an Offering will have no effect upon his or her eligibility to
participate in any subsequent Offering or in any employee stock purchase plan
(within the meaning of Section 423 of the Code) that may hereafter be adopted by
the Company or a Subsidiary.

11.  EXPIRATION OF OPTIONS ON TERMINATION OF EMPLOYMENT

     Options shall not be transferable by a Participant and no amount credited
to a Participant's account may be assigned, transferred, pledged or otherwise
disposed of in any way by a Participant.  An Option shall expire unexercised
immediately if a Participant ceases to satisfy the definition of the term
Employee for any reason other than death and the amount of the accumulated
payroll deductions then credited to the Participant's account under the Plan
will be paid in cash.  Upon termination of the Participant's employment with the
Company or a Subsidiary for any reason other than death, an amount in cash equal
to the accumulated payroll deductions then credited to the Participant's account
under the Plan will be paid to the Participant.  In the case of a Participant's
death, the provisions of Section 15 shall control.

     An authorized leave of absence or absence on military or government service
shall not constitute severance of the employment relationship between the
Company or Subsidiary and the Participant for purposes of this Section 11,
provided that either (a) the absence is for a period of no more than 90 days
or (b) the Employee's right to be re-employed after the absence is guaranteed
either by statute or by contract.

12.  REQUIREMENTS OF LAW

     The Company shall not be required to sell or issue any shares of Common
Stock under the Plan if the issuance of such shares would constitute or result
in a violation by the Optionee or the Company of any provision of any law,
statute or regulation of any governmental authority.  Specifically, in
connection with the Securities Act, upon the exercise of any Option the Company
shall not be required to issue shares unless the Board has received evidence
satisfactory to it to the effect that the Optionee will not transfer such shares
except pursuant to a registration statement in effect under the Securities Act
or unless an opinion of counsel satisfactory to the Company has been received by
the Company to the effect that such registration is not required.  Any
determination in this connection by the Board shall be final, binding and
conclusive.  The Company shall not be obligated to take any affirmative action
to cause the exercise of an Option or the issuance of shares pursuant to an
Option to comply with any laws or regulations of any governmental authority
including, without limitation, the Securities Act or applicable state securities
laws.

13.  NO RIGHTS AS STOCKHOLDER

     No Participant shall have rights as a stockholder with respect to shares
covered by his Option until the applicable Exercise Date and, except as
otherwise provided in Section 15, no adjustment shall be made for dividends of
which the record date precedes the applicable Exercise Date.

                                     - 6 -


14.  FORFEITURE FOR DISHONESTY

     Notwithstanding anything to the contrary in the Plan, if the Board
determines, after full consideration of the facts presented on behalf of both
the Company and the individual, that a Participant or an Optionee has been
engaged in fraud, embezzlement, theft, commission of a felony or proven
dishonesty in the course of the individual's employment by the Company or a
Subsidiary, or has disclosed trade secrets or other proprietary information of
the Company or a Subsidiary, (a) such individual's participation in an Offering
shall terminate and the individual shall forfeit the right to receive any Common
Stock pursuant to an Offering that has not yet been delivered and (b) the
Company shall have the right to repurchase all or any part of the shares of
Common Stock acquired by an Optionee upon the earlier exercise of any Option, at
a price equal to the amount paid to the Company upon such exercise, increased by
an amount equal to the interest that would have accrued in the period between
the date of exercise of the Option and the date of such repurchase upon a debt
in the amount of the exercise price, at the prime rate(s) announced from time to
time during such period in the Federal Reserve Statistical Release Selected
Interest Rates.  The decision of the Board as to the cause of a Participant's or
Optionee's discharge and the damage done to the Company or a Subsidiary shall be
final, binding and conclusive.  No decision of the Board, however, shall affect
in any manner the finality of the discharge of a Participant or Optionee by the
Company or a Subsidiary.

15.  CHANGES IN THE COMPANY'S CAPITAL STRUCTURE

    (a)  If the outstanding shares of Common Stock are hereafter changed for a
different number or kind of shares or other securities of the Company, by reason
of a reorganization, recapitalization, exchange of shares, stock split,
combination of shares or dividend payable in shares or other securities, a
corresponding adjustment shall be made by the Committee in the number and kind
of shares or other securities, and in the Option Price, covered by outstanding
Options, and for which Options may be granted under the Plan; provided, however,
that no adjustment shall be made that would constitute a modification as defined
in Section 424 of the Code. Any such adjustment made by the Committee shall be
conclusive and binding upon all affected persons, including the Company and all
Participants and Optionees.

    (b)  If while unexercised Options remain outstanding under the Plan the
Company merges or consolidates with a wholly-owned subsidiary for the purpose of
reincorporating itself under the laws of another jurisdiction, the Optionees
will be entitled to acquire shares of common stock of the reincorporated Company
upon the same terms and conditions as were in effect immediately prior to such
reincorporation (unless such reincorporation involves a change in the number of
shares or the capitalization of the Company, in which case proportional
adjustments shall be made as provided above), and the Plan, unless otherwise
rescinded by the Board, will remain the Plan of the reincorporated company.

    (c)  Except as otherwise provided in (a) or (b) above, if while unexercised
Options remain outstanding under the Plan the Company merges or consolidates
with one or more corporations (whether or not the Company is the surviving
corporation), or is liquidated or sells or otherwise disposes of substantially
all of its assets to another entity, then the Committee, in its discretion,
shall provide that either:

                                     - 7 -


         (i) after the effective date of such merger, consolidation,
   liquidation or sale, as the case may be, each Optionee shall be entitled,
   upon exercise of an Option to receive in lieu of shares of Common Stock the
   number and class of shares of such stock or other securities to which he
   would have been entitled pursuant to the terms of the merger, consolidation,
   liquidation or sale if he had been the holder of record of the number of
   shares of Common Stock as to which the Option is being exercised immediately
   prior to such merger consolidation, liquidation or sale; or

         (ii)  all outstanding Options shall be exercised as of the day
   preceding the effective date of any such merger, consolidation, liquidation
   or sale, which day shall be the Exercise Date for purposes of the Offering;
   provided, however, that each Optionee shall be notified of the right to
   withdraw from the Offering in accordance with the requirements of Section 10.

    (d)  Except as expressly provided to the contrary in this Section 15, the
issuance by the Company of shares of stock of any class for cash or property or
for services, either upon direct sale or upon the exercise of rights or
warrants, or upon conversion of shares or obligations of the Company convertible
into such shares or other securities, shall not affect the number, class or
price of shares of Common Stock then subject to outstanding Options.

16.  DISPOSITION OF ACCOUNT AT DEATH

     In the event that a Participant dies after the Exercise Date but before the
delivery of the stock certificates, such certificates when issued together with
any cash remaining in the Participant's account shall be transferred to the
Participant's estate.  In the event that a Participant dies prior to the
Exercise Date, a payment shall be made to the Participant's estate of an amount
in cash equal to the accumulated payroll deductions credited to the
Participant's account under the Plan; provided, however, that the executor,
administrator or personal representative of the estate of the Participant may by
notice to the Committee in the form and manner prescribed by the Committee
request that the balance of the Participant's account shall be used to exercise
on the Exercise Date the outstanding Option granted prior to the Participant's
death.  Any such election by the executor, administrator or personal
representative shall be made not later than the Exercise Date.  The Company
shall transfer such shares and any cash remaining in the Participant's account
to the executor, administrator or personal representative of the estate of the
Participant.

17.  MISCELLANEOUS

     (a) Accumulated payroll deductions and the proceeds from the sale of shares
pursuant to the exercise of Options shall constitute general funds of the
Company.

     (b) To the extent required by law, the Company or a Subsidiary shall
withhold or cause to be withheld income and other taxes with respect to any
income recognized by an Optionee by reason of the exercise of an Option. An
Optionee shall agree that if the amount payable to him by the Company and any
Subsidiary in the ordinary course is insufficient to pay such taxes, then he
shall upon request of the Company pay to the Company an amount sufficient to
satisfy its tax withholding obligations.

                                     - 8 -


(c)   All notices or other communications by a Participant or Optionee to the
Company pursuant to the Plan shall be deemed to have been given when received in
the form specified by the Company at the location or by the person designated by
the Company for the receipt thereof.

(d)   Neither the Plan nor the grant of an Option pursuant to the Plan shall
impose upon the Company or a Subsidiary any obligation to employ or continue to
employ any Participant, and the right of the Company or a Subsidiary to
terminate the employment of any person shall not be diminished or affected by
reason of the fact that an Option has been granted to him.

(e)   The title of the sections of the Plan are included for convenience only
and shall not be construed as modifying or affecting their provisions. The
masculine gender shall include both sexes; the singular shall include the plural
and the plural the singular unless the context otherwise requires.

(f)   The Plan shall be governed by and construed in accordance with the laws of
the Commonwealth of Massachusetts, without regard to the principles of conflicts
of law.

18.  AMENDMENT OR TERMINATION OF PLAN

     The Board may at any time terminate or from time to time amend, modify or
suspend this Plan (or any part thereof); provided, however, that without
approval by holders of a majority of the outstanding shares of common stock
present, or represented, and entitled to vote thereon (voting as a single class)
at a duly held meeting (or written consents in lieu thereof) of the shareholders
of the Company there shall be no:  (a) change in the number of shares of Common
Stock that may be issued under the Plan, except by operation of the provisions
of Section 15; (b) change in the class of persons eligible to participate in the
Plan; or (c) other change in the Plan that requires stockholder approval under
applicable law. Notwithstanding the preceding sentence, the Board shall in all
events have the power to make such changes in the Plan and the Committee shall
in all events have the power to make such changes in the regulations and
administrative provisions under the Plan or in any outstanding Option as, in the
opinion of counsel for the Company, may be necessary or appropriate from time to
time to enable the Plan to qualify as an employee stock purchase plan as defined
in Section 423 of the Code, so as to enable any Option to receive preferential
federal income tax treatment. No amendment shall materially affect outstanding
Options without the consent of the Optionee and the termination of the Plan will
not terminate Options then outstanding, without the consent of the Optionee.

     Notwithstanding the foregoing, at such time after the Company is not
required to file periodic reports under the Exchange Act, at its option, the
Company may terminate the Plan and, upon the termination, outstanding Options
shall be cancelled and each Participant shall receive in cash an amount equal to
the accumulated payroll deductions without interest credited to the
Participant's account under the Plan immediately prior to termination.

                                     - 9 -


19.  EFFECTIVE DATE AND DURATION OF THE PLAN

     The Plan shall be effective as of July 1, 2000, subject only to
ratification by the holders of a majority of the outstanding shares of common
stock present, or represented, and entitled to vote thereon (voting as a single
class) at a duly held meeting (or written consents in lieu thereof) of the
shareholders of the Company within 12 months before or after such date. Unless
the Plan shall have terminated earlier, the Plan shall terminate on the business
date as of which there are no longer any shares available pursuant to Section 4
to be offered and no Option shall be granted pursuant to the Plan after that
date.

                                     - 10 -


                                                                         ANNEX B







================================================================================

                              ATC TELEPORTS, INC.

                             1999 Stock Option Plan

================================================================================


                               Table of Contents
                               -----------------
                                                                            Page
                                                                            ----
 1.  PURPOSE................................................................   1

 2.  ADMINISTRATION OF THE PLAN.............................................   1

 3.  OPTION SHARES..........................................................   2

 4.  AUTHORITY TO GRANT OPTIONS.............................................   2

 5.  WRITTEN AGREEMENT......................................................   2

 6.  ELIGIBILITY............................................................   2

 7.  OPTION PRICE...........................................................   3

 8.  DURATION OF OPTIONS....................................................   3

 9.  VESTING PROVISIONS.....................................................   3

10.  EXERCISE OF OPTIONS....................................................   4

11.  TRANSFERABILITY OF OPTIONS.............................................   5

12.  TERMINATION OF EMPLOYMENT OR INVOLVEMENT OF OPTIONEE WITH THE
     COMPANY................................................................   5

13.  REQUIREMENTS OF LAW....................................................   6

14.  NO RIGHTS AS STOCKHOLDER...............................................   6

15.  EMPLOYMENT OBLIGATION..................................................   6

16.  FORFEITURE AS A RESULT OF TERMINATION FOR CAUSE........................   7

17.  CHANGES IN THE COMPANY'S CAPITAL STRUCTURE.............................   7

18.  AMENDMENT OR TERMINATION OF PLAN.......................................   8

19.  CERTAIN RIGHTS OF THE COMPANY..........................................   9

20.  GOVERNING LAW..........................................................  10

21.  EFFECTIVE DATE AND DURATION OF THE PLAN................................  10


                                       i


                              ATC TELEPORTS, INC.

                             1999 STOCK OPTION PLAN

     1. PURPOSE

     The purpose of this 1999 Stock Option Plan (the "Plan") is to encourage
directors, officers and employees of and consultants and other persons providing
services to ATC Teleports, Inc. (the "Company") and its Affiliates (as
hereinafter defined) to continue their association with the Company and its
Subsidiaries, by providing opportunities for such persons to participate in the
ownership of the Company and in its future growth through the granting of stock
options (the "Options") which may be options designed to qualify as incentive
stock options (within the meaning of Section 422 of the Internal Revenue Code of
1986, as amended (the "Code") (an "ISO"), or Options not intended to qualify for
any special tax treatment under the Code (a "NQO").  The term "Affiliate" as
used in the Plan means a corporation or other business organization which owns
in the Company, or in which the Company or any such corporation or other
business entity owns, directly or indirectly through an unbroken chain of
ownership, fifty percent (50%) or more of the total combined voting power of all
classes of stock.

     2. ADMINISTRATION OF THE PLAN

     The Plan shall be administered by a committee (the "Committee") consisting
of two or more members of the Company's Board of Directors (the "Board").  The
Committee shall from time to time determine to whom options or other rights
shall be granted under the Plan, whether options granted shall be ISOs or NQOs,
the terms of the options or other rights, and the number of shares that may be
granted under options.  The Committee shall report to the Board the names of
individuals to whom stock or options or other rights are to be granted, the
number of shares covered, and the terms and conditions of each grant.  The
determinations described in this Section 2 may be made by the Committee or by
the Board, as the Board shall direct in its sole and absolute discretion, and
references in the Plan to the Committee shall be understood to refer to the
Board in any such case.

     The Committee shall select one of its members as Chairman and shall hold
meetings at such times and places as it may determine.  A majority of the
Committee shall constitute a quorum, and acts of the Committee at which a quorum
is present, or acts reduced to or approved in writing by all the members of the
Committee, shall be the valid acts of the Committee.  The Committee shall have
the authority to adopt, amend, and rescind such rules and regulations as, in its
opinion, may be advisable in the administration of the Plan.  All questions of
interpretation and application of such rules and regulations, of the Plan and of
Options, shall be subject to the determination of the Committee, which shall be
final and binding.  The Plan shall be administered in such a manner as to permit
those Options granted hereunder and specially designated under Section 5 as ISOs
to qualify as incentive stock options as described in Section 422 of the
Internal Revenue Code of 1986, as amended (the "Code").

     For so long as Section 16 of the Securities Exchange Act of 1934, as
amended from time to time (the "Exchange Act"), is applicable to the Company,
each member of the Committee shall be a "non-employee director" or the
equivalent within the meaning of Rule 16b-3 under the Exchange Act, and, for so
long as Section 162(m) of the Code is applicable to the Company, an "outside
director" within the meaning of Section 162 of the Code and the regulations
thereunder.  If, however, the Committee is not comprised of two or more "outside
directors," then, although the Committee may still administer the Plan, the
Compensation Committee of the Board of Directors of American Tower Corporation,
so long as it is the parent of the Company, or such other committee that makes
grants pursuant to the parent's stock option or similar plan, shall make grants
of options or other rights under the Plan (if the Compensation Committee or such
committee consists of two or more members who are "outside directors").


     With respect to persons subject to Section 16 of the Exchange Act
("Insiders"), transactions under the Plan are intended to comply with all
applicable conditions of Rule 16b-3 or its successor under the Exchange Act.  To
the extent any provision of the Plan or action by the Committee fails to so
comply, it shall be deemed to be modified so as to be in compliance with such
Rule, or, if such modification is not possible, it shall be deemed to be null
and void, to the extent permitted by law and deemed advisable by the Committee.

     3. OPTION SHARES

     The stock subject to Options under the Plan shall be shares of Common
Stock, par value $.01 per share (the "Stock").  The total amount of the Stock
with respect to which Options may be granted (the "Option Pool"), shall not
exceed in the aggregate 1,000,000 shares; provided, however, such aggregate
number of shares shall be subject to adjustment in accordance with the
provisions of Section 17.  If an outstanding Option shall expire for any reason
or shall terminate by reason of the death or severance of employment of the
Optionee, the surrender of any such Option, or any other cause, the shares of
Stock allocable to the unexercised portion of such Option may again be subject
to an option under the Plan. The maximum number of shares of Stock subject to
Options that may be granted to any Optionee in the aggregate in any calendar
year shall not exceed 500,000 shares, subject to adjustment in accordance with
the provisions of Section 17.

     4. AUTHORITY TO GRANT OPTIONS

     The Committee may determine, from time to time, which employees of the
Company or any Affiliate or other persons shall be granted Options under the
Plan, the terms of the Options (including without limitation whether an Option
shall be an ISO or a NQO) and the number of shares which may be purchased under
the Option or Options.  Without limiting the generality of the foregoing, the
Committee may from time to time grant:  (a) to such employees (other than
employees of an Affiliate which is not a corporation) as it shall determine an
Option or Options to buy a stated number of shares of Stock under the terms and
conditions of the Plan which Option or Options will to the extent so designated
at the time of grant constitute an ISO; and (b) to such eligible directors,
employees or other persons as it shall determine an Option or Options to buy a
stated number of shares of Stock under the terms and conditions of the Plan
which Option or Options shall constitute a NQO.  Subject only to any applicable
limitations set forth elsewhere in the Plan, the number of shares of Stock to be
covered by any Option shall be as determined by the Committee.

     5. WRITTEN AGREEMENT

     Each Option granted hereunder shall be embodied in an option agreement (the
"Option Agreement") substantially in the form of Exhibit 1, which shall be
signed by the Optionee and by the Chief Executive Officer, the Chief Operating
Officer, Chief Financial Officer, the General Counsel or the Corporate
Controller of the Company for and in the name and on behalf of the Company.  An
Option Agreement may contain such restrictions on exercisability and such other
provisions not inconsistent with the Plan as the Committee in its sole and
absolute discretion shall approve.

     6. ELIGIBILITY

     The individuals who shall be eligible for grant of Options under the Plan
shall be employees (including officers who may be members of the Board),
directors who are not employees and other individuals, whether or not employees,
who render services of special importance to the management, operation or
development of the Company or an Affiliate, and who have contributed or may be
expected to contribute to the success of the Company or an Affiliate.  An
employee, director or other person to

                                      -2-


whom an Option has been granted pursuant to an Option Agreement is hereinafter
referred to as an "Optionee."

     7. OPTION PRICE

     The price at which shares of Stock may be purchased pursuant to an Option
shall be specified by the Committee at the time the Option is granted, but shall
in no event be less than the par value of such shares and, in the case of an
ISO, except as set forth in the following sentence, one hundred percent (100%)
of the fair market value of the Stock on the date the ISO is granted.  In the
case of an employee who owns (or is considered under Section 424(d) of the Code
as owning) stock possessing more than ten percent (10%) of the total combined
voting power of all classes of stock of the Company or any Affiliate, the price
at which shares of Stock may be so purchased pursuant to an ISO shall be not
less than one hundred and ten percent (110%) of the fair value of the Stock on
the date the ISO is granted.

     For purposes of the Plan, the "fair market value" of a share of Stock on
any date specified herein, shall mean (a) the last reported sales price, regular
way, or, in the event that no sale takes place on such day, the average of the
reported closing bid and asked prices, regular way, in either case (i) as
reported on the New York Stock Exchange Composite Tape, or (ii) if the Stock is
not listed or admitted to trading on the New York Stock Exchange, on the
principal national securities exchange on which such security is listed or
admitted to trading, or (iii) if not then listed or admitted to trading on any
national securities exchange, on the NASDAQ National Market System; or (b) if
the Stock is not quoted on such National Market System, (i) the average of the
closing bid and asked prices on each such day in the over-the-counter market as
reported by NASDAQ, or (ii) if bid and asked prices for such security on each
such day shall not have been reported through NASDAQ, the average of the bid and
asked prices for such day as furnished by any New York Stock Exchange member
firm regularly making a market in such security selected for such purpose by the
Committee; or (c) if the Stock is not then listed or admitted to trading on any
national exchange or quoted in the over-the-counter market, the fair value
thereof determined in good faith by the Committee (which shall be entitled to
take into account that the Stock may be illiquid, may be subject to restrictions
on transfer or may constitute a minority interest in the Company); provided,
however, that any method of determining fair market value employed by the
Committee with respect to an ISO shall be consistent with any applicable laws or
regulations pertaining to "incentive stock options."

     8. DURATION OF OPTIONS

     The duration of any Option shall be specified by the Committee in the
Option Agreement, but no Option shall be exercisable after the expiration of ten
(10) years from the date such Option is granted.  In the case of any employee
who owns (or is considered under Section 424(d) of the Code as owning) stock
possessing more than ten percent (10%) of the total combined voting power of all
classes of stock of the Company or any Affiliate, no ISO shall be exercisable
after the expiration of five (5) years from the date such Option is granted.
The Committee, in its sole and absolute discretion, may extend any Option
theretofore granted.

     9. VESTING PROVISIONS

     Each Option may be exercised so long as it is valid and outstanding from
time to time, in part or as a whole, in such manner and subject to such
conditions as the Committee, in its sole and absolute discretion, may provide in
the Option Agreement.  The Committee may, in its sole and absolute discretion,
accelerate Options, in whole or in part, on such terms and conditions as the
Committee may, in its sole and absolute discretion, determine.

                                      -3-


     10. EXERCISE OF OPTIONS

     Options shall be exercised by the delivery of written notice to the Company
setting forth the number of shares of Stock with respect to which the Option is
to be exercised, accompanied by payment of the option price of such shares,
which payment shall be made, subject to the alternative provisions of this
Section, in cash or by such cash equivalents, payable to the order of the
Company in an amount in United States dollars equal to the option price of such
shares, as the Committee in its sole and absolute discretion shall consider
acceptable.  Such notice shall be delivered in person to the Secretary of the
Company or shall be sent by registered mail, return receipt requested, to the
Secretary of the Company, in which case delivery shall be deemed made on the
date such notice is deposited in the mail.

     Alternatively, if the Option Agreement so specifies, and subject to such
rules as may be established by the Committee, payment of the option price may be
made through a so-called "cashless exercise" procedure, under which the Optionee
shall deliver irrevocable instructions to a broker to sell shares of Stock
acquired upon exercise of the Option and to remit promptly to the Company a
sufficient portion of the sale proceeds to pay the option price and any tax
withholding resulting from such exercise.

     Alternatively, payment of the option price may be made, in whole or in
part, in shares of Stock owned by the Optionee; provided, however, that the
Optionee may not make payment in shares of Stock that he acquired upon the
earlier exercise of any ISO (or other "incentive stock option"), unless and
until he has held the shares until at least two (2) years after the date the ISO
(or such other incentive stock option) was granted and at least one (1) year
after the date the ISO (or such other option) was exercised.  If payment is made
in whole or in part in shares of Stock, then the Optionee shall deliver to the
Company in payment of the option price of the shares with respect of which such
Option is exercised (a) certificates registered in the name of such Optionee
representing a number of shares of Stock legally and beneficially owned by such
Optionee, free of all liens, claims and encumbrances of every kind, and having a
fair market value on the date of delivery of such notice equal to the option
price of the shares of Stock with respect to which such Option is to be
exercised, such certificates to be accompanied by stock powers duly endorsed in
blank by the record holder of the shares of Stock represented by such
certificates; and (b) if the option price of the shares with respect to which
such Option is to be exercised exceeds such fair market value, cash or such cash
equivalents payable to the order to the Company, in an amount in United States
dollars equal to the amount of such excess, as the Committee in its sole and
absolute discretion shall consider acceptable.  Notwithstanding the foregoing
provisions of this Section, the Committee, in its sole and absolute discretion,
(i) may refuse to accept shares of Stock in payment of the option price of the
shares of Stock with respect to which such Option is to be exercised and, in
that event, any certificates representing shares of Stock which were delivered
to the Company with such written notice shall be returned to such Optionee
together with notice by the Company to such Optionee of the refusal of the
Committee to accept such shares of Stock and (ii) may accept, in lieu of actual
delivery of stock certificates, an attestation by the Optionee substantially in
the form attached herewith as Exhibit C or such other form as may be deemed
acceptable by the Committee that he or she owns of record the shares to be
tendered free and clear of all liens, claims and encumbrances of every kind.

     Alternatively, if the Option Agreement so specifies, payment of the option
price may be made in part by a full recourse promissory note executed by the
Optionee and containing the following terms and conditions (and such others as
the Committee shall, in its sole and absolute discretion, determine from time to
time):  (a) it shall be collaterally secured by the shares of Stock obtained
upon exercise of the Option; (b) repayment shall be made on demand by the
Company and, in any event, no later than three (3) years from the date of
exercise; and (c) the note shall bear interest at a rate as determined by the
Committee, payable monthly out of a payroll deduction provision; provided,
however, that notwithstanding the foregoing (i) an amount not less than the par
value of the shares of Stock with respect to which the Option is being exercised
must be paid in cash, cash equivalents, or shares of Stock in accordance with
this Section, and (ii) the payment of such exercise price by promissory note
does not

                                      -4-


violate any applicable laws or regulations, including, without limitation,
Delaware corporate law or applicable margin lending rules. The decision as to
whether to permit partial payment by a promissory note for shares of Stock to be
issued upon exercise of any Option granted shall rest entirely in the sole and
absolute discretion of the Committee.

     As promptly as practicable after the receipt by the Company of (a) written
notice from the Optionee setting forth the number of shares of Stock with
respect to which such Option is to be exercised and (b) payment of the option
price of such shares in the form required by the foregoing provisions of this
Section, the Company shall cause to be delivered to such Optionee certificates
representing the number of shares with respect to which such Option has been so
exercised (less a number of shares equal to the number of shares as to which
ownership was attested under the procedure described in clause (ii) of the next
preceding paragraph).

     11. TRANSFERABILITY OF OPTIONS

     Options shall not be transferable by the Optionee otherwise than by will or
under the laws of descent and distribution, and shall be exercisable during his
or her lifetime only by the Optionee, except that the Committee may, subject to
such conditions as it shall, in its sole and absolute discretion, determine,
specify in an Option Agreement that pertains to an NQO that the Optionee may
transfer such NQO to a member of the Immediate Family of the Optionee, to a
trust solely for the benefit of the Optionee and the Optionee's Immediate
Family, or to a partnership or limited liability company whose only partners or
members are the Optionee and members of the Optionee's Immediate Family.
"Immediate Family" shall mean, with respect to any Optionee, such Optionee's
child, stepchild, grandchild, parent, stepparent, grandparent, spouse, sibling,
mother-in-law, father-in-law, son-in-law, daughter-in-law, brother-in-law, or
sister-in-law, and shall include adoptive relationships.

     12. TERMINATION OF EMPLOYMENT OR INVOLVEMENT OF OPTIONEE WITH THE COMPANY

     For purposes of this Section, employment by or involvement with (in the
case of an Optionee who is not an employee) an Affiliate shall be considered
employment by or involvement with the Company.  Except as otherwise set forth in
the Option Agreement, after the Optionee's termination of employment with the
Company other than by reason of death or disability, including his retirement in
good standing from the employ of the Company for reasons of age under the then
established rules of the Company, the Option shall terminate on the earlier of
the date of its expiration or three (3) months after the date of such
termination or retirement.  After the death of the Optionee, his or her
executors, administrators or any persons to whom his or her Option may be
transferred by will or by the laws of descent and distribution shall have the
right to exercise the Option to the extent to which the Optionee was entitled to
exercise the Option.  The Committee may, subject to such conditions as it shall,
in its sole and absolute discretion, determine, specify in an Option Agreement
that, in the event that such termination is a result of disability, the Optionee
shall have the right to exercise the Option pursuant to its terms as if such
Optionee continued as an employee; provided, however, that any such Option that
is an ISO shall, in order to preserve its status as such, be required to be
exercised with twelve (12) months of such termination.

     Authorized leave of absence or absence on military or government service
shall not constitute severance of the employment relationship between the
Company and the Optionee for purposes of the Plan, provided that either (a) such
absence is for a period of no more than ninety (90) days or (b) the Employee's
right to re-employment after such absence is guaranteed either by statute or by
contract.

                                      -5-


     For Optionees who are not employees of the Company, options shall be
exercisable for such periods following the termination of the Optionee's
involvement with the Company as may be set forth in the Option Agreement.

     13. REQUIREMENTS OF LAW

     The Company shall not be required to sell or issue any shares of Stock upon
the exercise of any Option if the issuance of such shares shall constitute or
result in a violation by the Optionee or the Company of any provisions of any
law, statute or regulation of any governmental authority.  Specifically, in
connection with the Securities Act of 1933, as amended (the "Securities Act"),
and any applicable state securities or "blue sky" law (a "Blue Sky Law"), upon
exercise of any Option the Company shall not be required to issue such shares
unless the Committee has received evidence satisfactory to it to the effect that
the holder of such Option will not transfer such shares except pursuant to a
registration statement in effect under the Securities Act and Blue Sky Laws or
unless an opinion of counsel satisfactory to the Company has been received by
the Company to the effect that such registration and compliance is not required.
Any determination in this connection by the Committee shall be final, binding
and conclusive.  The Company shall not be obligated to take any action in order
to cause the exercise of an Option or the issuance of shares of Stock pursuant
thereto to comply with any law or regulations of any governmental authority,
including, without limitation, the Securities Act or applicable Blue Sky Law.

     Notwithstanding any other provision of the Plan to the contrary, the
Company may refuse to permit transfer of shares of Stock if in the opinion of
its legal counsel such transfer would violate federal or state securities laws
or subject the Company to liability thereunder.  Any sale, assignment, transfer,
pledge or other disposition of shares of Stock received upon exercise of any
Option (or any other shares or securities derived therefrom) which is not in
accordance with the provisions of this Section shall be void and of no effect
and shall not be recognized by the Company.

     Legend on Certificates.  The Committee may cause any certificate
     ----------------------
representing shares of Stock acquired upon exercise of an Option (and any other
shares or securities derived therefrom) to bear a legend to the effect that the
securities represented by such certificate have not been registered under the
Securities Act of 1933, as amended, or any applicable state securities laws, and
may not be sold, assigned, transferred, pledged or otherwise disposed of except
in accordance with the Plan and applicable agreements binding the holder and the
Company or any of its stockholders.

     14. NO RIGHTS AS STOCKHOLDER

     No Optionee shall have any rights as a stockholder with respect to shares
covered by his or her Option until the date of issuance of a stock certificate
for such shares; except as otherwise provided in Section 17, no adjustment for
dividends or otherwise shall be made if the record date therefor is prior to the
date of issuance of such certificate.

     15. EMPLOYMENT OBLIGATION

     The granting of any Option shall not impose upon the Company or any
Affiliate any obligation to employ or continue to employ any Optionee, or to
engage or retain the services of any person, and the right of the Company or any
Affiliate to terminate the employment or services of any person shall not be
diminished or affected by reason of the fact that an Option has been granted to
him or her.  The existence of any Option shall not be taken into account in
determining any damages relating to termination of employment or services for
any reason.

                                      -6-


     16. FORFEITURE AS A RESULT OF TERMINATION FOR CAUSE

     Notwithstanding any provision of the Plan to the contrary, if the Committee
determines, after full consideration of the facts presented on behalf of the
Company and an Optionee, that

          (a)  the Optionee has been engaged in fraud, embezzlement, theft,
     commission of a felony or dishonesty in the course of his or her employment
     by or involvement with the Company or an Affiliate, which damaged the
     Company or an Affiliate, or has made unauthorized disclosure of trade
     secrets or other proprietary information of the Company or an Affiliate or
     of a third party who has entrusted such information to the Company or an
     Affiliate, or

          (b)  the Optionee's employment or involvement was otherwise terminated
     for "cause," as defined in any employment agreement with the Optionee, if
     applicable, or if there is no such agreement, as determined by the
     Committee, which may determine that "cause" includes among other matters
     the willful failure or refusal of the Optionee to perform and carry out his
     or her assigned duties and responsibilities diligently and in a manner
     satisfactory to the Committee, or the material breach by the Optionee of
     any rules of conduct, policies or regulations of the Company or any
     Affiliate,

then the Optionee's right to exercise an Option shall terminate as of the date
of such act (in the case of (a)) or such termination (in the case of (b)) and
the Optionee shall forfeit all unexercised Options.  If an Optionee whose
behavior the Company asserts falls within the provisions of (a) or (b) above has
exercised or attempts to exercise an Option prior to a decision of the
Committee, the Company shall not be required to recognize such exercise until
the Committee has made its decision and, in the event of any exercise shall have
taken place, it shall be of no force and effect (and void ab initio) if the
Committee makes an adverse determination; provided, however, if the Committee
finds in favor of the Optionee then the Optionee will be deemed to have
exercised such Option retroactively as of the date he or she originally gave
written notice of his or her attempt to exercise or actual exercise, as the case
may be.  The decision of the Committee as to the cause of an Optionee's
discharge and the damage done to the Company or an Affiliate shall be final,
binding and conclusive.  No decision of the Committee, however, shall affect in
any manner the finality of the discharge of such Optionee by the Company or an
Affiliate.

     17. CHANGES IN THE COMPANY'S CAPITAL STRUCTURE

     The existence of outstanding Options shall not affect in any way the right
or power of the Company or its stockholders to make or authorize any or all
adjustments, recapitalizations, reorganizations or other changes in the
Company's capital structure or its business or any merger or consolidation of
the Company or any issue of bonds, debentures, preferred or preference stock,
whether or not convertible into the Stock or other securities, ranking prior to
the Stock or affecting the rights thereof, or warrants, rights or options to
acquire the same, or the dissolution or liquidation of the Company or any sale
or transfer of all or any part of its assets or business or any other corporate
act or proceeding, whether of a similar character or otherwise.

     The number of shares of Stock in the Option Pool (less the number of shares
theretofore delivered upon exercise of Options) and the number of shares of
Stock covered by any outstanding Option and the price per share payable upon
exercise thereof (provided that in no event shall the option price be less than
the par value of such shares) shall be proportionately adjusted for any increase
or decrease in the number of issued and outstanding shares of Stock resulting
from any subdivision, split, combination or consolidation of shares of Stock or
the payment of a dividend in shares of stock or other securities of the Company
on the Stock.  The decision of the Board as to the adjustment, if any, required
by the provisions of this Section shall be final, binding and conclusive.

                                      -7-


     If the Company merges or consolidates with a wholly-owned subsidiary for
the purpose of reincorporating itself under the laws of another jurisdiction,
the Optionees will be entitled to acquire shares of Stock of the reincorporated
Company upon the same terms and conditions as were in effect immediately prior
to such reincorporation (unless such reincorporation involves a change in the
number of shares or the capitalization of the Company, in which case
proportional adjustments shall be made as provided above) and the Plan, unless
otherwise rescinded by the Board, will remain the Plan of the reincorporated
Company.

     Except as otherwise provided in the preceding paragraph, if the Company is
merged or consolidated with another corporation, whether or not the Company is
the surviving entity, or if the Company is liquidated or sells or otherwise
disposes of all or substantially all of its assets to another entity while
unexercised Options remain outstanding under the Plan, or if other circumstances
occur in which the Board in its sole and absolute discretion deems it
appropriate for the provisions of this paragraph to apply (in each case, an
"Applicable Event"), then (a) each holder of an outstanding Option shall be
entitled, upon exercise of such Option, to receive in lieu of shares of Stock,
such stock or other securities or property as he or she would have received had
he exercised such option immediately prior to the Applicable Event;  (b) the
Board may, in its sole and absolute discretion, waive, generally or in one or
more specific cases, any limitations imposed pursuant to Section 9 so that some
or all Options from and after a date prior to the effective date of such
Applicable Event, specified by the Board, in its sole and absolute discretion,
shall be exercisable in full or in part; (c) the Board may, in its sole and
absolute discretion, cancel all outstanding and unexercised Options as of the
effective date of any such Applicable Event; (d) the Board may, in its sole
discretion, convert some or all Options into options to purchase the stock or
other securities of the surviving corporation pursuant to an Applicable Event;
or (e) the Board may, in its sole and absolute discretion, assume the
outstanding and unexercised options to purchase stock or other securities of any
corporation and convert such options into Options to purchase Stock, whether
pursuant to this Plan or not, pursuant to an Applicable Event; provided,
however, notice of any such cancellation pursuant to clause (c) shall be given
to each holder of an Option not less than thirty (30) days preceding the
effective date of such Applicable Event, and provided further, however, that the
Board may, in its sole and absolute discretion, waive, generally or in one or
more specific instances, any limitations imposed pursuant to Section 9 with
respect to any Option so that such Option shall be exercisable in full or in
part, during such thirty (30) day period.

     Except as expressly provided herein, the issue by the Company of shares of
Stock or other securities of any class or series or securities convertible into
or exchangeable or exercisable for shares of Stock or other securities of any
class or series for cash or property or for labor or services either upon direct
sale or upon the exercise of rights or warrants to subscribe therefor, or upon
conversion of shares or obligations of the Company convertible into such shares
or other securities, shall not affect, and no adjustment by reason thereof shall
be made with respect to, the number, class or price of shares of Stock then
subject to outstanding Options.

     18. AMENDMENT OR TERMINATION OF PLAN

     The Board may, in its sole and absolute discretion, modify, revise or
terminate the Plan at any time and from time to time; provided, however, that
without the further approval of the holders of at least a majority of the
outstanding shares of Stock, the Board may not change the aggregate number of
shares of Stock which may be issued under Options pursuant to the provisions of
the Plan either to any one person or in the aggregate; or change the class of
persons eligible to receive ISOs.  Notwithstanding the preceding sentence, the
Board shall in all events have the power and authority to make such changes in
the Plan and in the regulations and administrative provisions hereunder or in
any outstanding Option as, in the opinion of counsel for the Company, may be
necessary or appropriate from time to time to enable any Option granted pursuant
to the Plan to qualify as an incentive stock option or such other stock option

                                      -8-


as may be defined under the Code, as amended from time to time, so as to receive
preferential federal income tax treatment.

     19. CERTAIN RIGHTS OF THE COMPANY

     Voluntary or Involuntary Transfers of Stock.  Except as may be set forth in
     -------------------------------------------
any applicable Optionee/Stockholder Agreement, shares of Stock acquired by an
Optionee pursuant to the exercise of an Option or Options granted under the Plan
shall not be voluntarily transferred by the Optionee without the prior written
consent of the Committee, which consent may be withheld or conditioned as the
Committee, in its sole and absolute discretion, determine.  If such shares of
Stock are subject to an involuntary transfer, including by reason of death, a
divorce settlement or judicial proceeding, the Company shall have the assignable
right to repurchase all or any such shares (including any shares of other
securities of the Company derived therefrom) at a price equal to the Repurchase
Price at the time of the involuntary transfer event.  The Company may exercise
its repurchase right no earlier than one hundred eighty (180) days after the
exercise of the Option (or one or more such exercises) and no later than three
hundred and sixty-five (365) days following the later of (a) the date of such
involuntary transfer of such shares of Stock, and (b) the Committee's receipt of
written notice of the occurrence of such transfer event.  Any such shares of
Stock (or other shares or securities) as to which the Company does not exercise
its repurchase rights within such period shall thereafter be free of the
foregoing restrictions.

     Termination of Employment or Involvement.  If the Optionee's employment by
     ----------------------------------------
or involvement with the Company (including, for this purpose, any Affiliate)
shall terminate for any reason other than the Optionee's death or a Justifiable
Termination (as defined below) or Optionee's retirement for reasons of age or
disability in accordance with the then policy of the Company, the Company shall
have the right to repurchase all or any of such shares of Stock (or other shares
or securities derived therefrom) at a price equal to the Repurchase Price at the
time of such repurchase.  In addition, if at the time of such termination an
Optionee holds an Option granted under the Plan which is by its terms
exercisable after such termination, the Company shall have the assignable right
to repurchase all or any part of the shares of Stock acquired pursuant to the
exercise of such Option, at the Repurchase Price at the time of such repurchase.
In the case of a termination on account of any circumstance listed in Section
16(a) or (b) (a "Justifiable Termination"), the Company shall have the right to
repurchase all or any of such shares of Stock at the lesser of (i) the exercise
price per share or (ii) the Repurchase Price at the time of such repurchase.  If
the option price for any repurchased shares has been paid by the Optionee's
promissory note pursuant to Section 10, then the repurchase price for such
shares of Stock shall be first applied to the repayment of the outstanding
amount, if any, due under such note in respect of the repurchased shares, and
any accrued but unpaid interest thereon.   The Company's right to repurchase
shares of Stock (or other shares or securities) may be exercised at any time no
later than three hundred and sixty-five (365) days following the date of the
Optionee's termination of employment or involvement.  Any such shares of Stock
(or other shares or securities) as to which the Company does not exercise its
repurchase rights within such period shall thereafter be free of the foregoing
restrictions.

     Repurchase Price.  As used herein the term "Repurchase Price" shall mean
     ----------------
the fair market value of a share of Stock (or other shares or securities) as
determined in accordance with the provisions of Section 7, except that in making
its determination of fair market value of a share of Stock the Committee shall
be entitled to take into account that the shares of Stock (or other shares and
securities) may be illiquid, may be subject to restrictions on transfer or may
constitute a minority interest in the Company.

     Stockholder Agreement.  Unless the Committee shall, in its sole and
     ---------------------
absolute discretion otherwise determine, it shall be a condition of each
Optionee receiving any shares of Stock upon any exercise of an Option that he or
she shall enter into the Optionee/Stockholder Agreement, a copy of which has
heretofore been delivered to the Optionee.

                                      -9-


     Other Provisions.  The Committee may, in its sole and absolute discretion,
     ----------------
require a key employee, as a condition to receiving any option, to enter into a
noncompetition agreement in such form as the Committee may, from time to time in
its sole and absolute discretion, determine.

     20. GOVERNING LAW

     The Plan shall be governed by and construed and enforced in accordance with
the applicable laws of the United States of America and the law (other than the
law governing conflict of law questions) of The Commonwealth of Massachusetts
except to the extent the laws of any other jurisdiction are mandatorily
applicable.

     21. EFFECTIVE DATE AND DURATION OF THE PLAN

     The Plan shall become effective and shall be deemed to have been adopted on
November 10, 1999.  Unless the Plan shall have terminated earlier, the Plan
shall terminate on the tenth (10th) anniversary of its effective date, and no
Option shall be granted pursuant to the Plan after the day preceding the tenth
(10th) anniversary of its effective date.

                                      -10-


                                                                         ANNEX C






================================================================================

                          KLINE IRON & STEEL CO., INC.

                             2000 Stock Option Plan

================================================================================


                               Table of Contents
                               -----------------

                                                                            Page
                                                                            ----

1.   PURPOSE................................................................   1

2.   ADMINISTRATION OF THE PLAN.............................................   1

3.   OPTION SHARES..........................................................   2

4.   AUTHORITY TO GRANT OPTIONS.............................................   2

5.   WRITTEN AGREEMENT......................................................   2

6.   ELIGIBILITY............................................................   2

7.   OPTION PRICE...........................................................   3

8.   DURATION OF OPTIONS....................................................   3

9.   VESTING PROVISIONS.....................................................   3

10.  EXERCISE OF OPTIONS....................................................   3

11.  TRANSFERABILITY OF OPTIONS.............................................   5

12.  TERMINATION OF EMPLOYMENT OR INVOLVEMENT OF OPTIONEE WITH THE COMPANY..   5

13.  REQUIREMENTS OF LAW....................................................   6

14.  NO RIGHTS AS STOCKHOLDER...............................................   6

15.  EMPLOYMENT OBLIGATION..................................................   6

16.  FORFEITURE AS A RESULT OF TERMINATION FOR CAUSE........................   6

17.  CHANGES IN THE COMPANY'S CAPITAL STRUCTURE.............................   7

18.  AMENDMENT OR TERMINATION OF PLAN.......................................   8

19.  CERTAIN RIGHTS OF THE COMPANY..........................................   8

20.  GOVERNING LAW..........................................................   9

21.  EFFECTIVE DATE AND DURATION OF THE PLAN................................  10


                                       i


                          KLINE IRON & STEEL CO., INC.

                             2000 STOCK OPTION PLAN

     1. PURPOSE

     The purpose of this 2000 Stock Option Plan (the "Plan") is to encourage
directors, officers and employees of and consultants and other persons providing
services to Kline Iron & Steel Co., Inc. (the "Company") and its Affiliates (as
hereinafter defined) to continue their association with the Company and its
Subsidiaries, by providing opportunities for such persons to participate in the
ownership of the Company and in its future growth through the granting of stock
options (the "Options") which may be options designed to qualify as incentive
stock options (within the meaning of Section 422 of the Internal Revenue Code of
1986, as amended (the "Code")) (an "ISO"), or Options not intended to qualify
for any special tax treatment under the Code (a "NQO").  The term "Affiliate" as
used in the Plan means a corporation or other business organization which owns
in the Company, or in which the Company or any such corporation or other
business entity owns, directly or indirectly through an unbroken chain of
ownership, fifty percent (50%) or more of the total combined voting power of all
classes of stock.

     2. ADMINISTRATION OF THE PLAN

     The Plan shall be administered by a committee (the "Committee") consisting
of two or more members of the Company's Board of Directors (the "Board").  The
Committee shall from time to time determine to whom options or other rights
shall be granted under the Plan, whether options granted shall be ISOs or NQOs,
the terms of the options or other rights, and the number of shares that may be
granted under options.  The Committee shall report to the Board the names of
individuals to whom stock or options or other rights are to be granted, the
number of shares covered, and the terms and conditions of each grant.  The
determinations described in this Section 2 may be made by the Committee or by
the Board, as the Board shall direct in its sole and absolute discretion, and
references in the Plan to the Committee shall be understood to refer to the
Board in any such case.

     The Committee shall select one of its members as Chairman and shall hold
meetings at such times and places as it may determine.  A majority of the
Committee shall constitute a quorum, and acts of the Committee at which a quorum
is present, or acts reduced to or approved in writing by all the members of the
Committee, shall be the valid acts of the Committee.  The Committee shall have
the authority to adopt, amend, and rescind such rules and regulations as, in its
opinion, may be advisable in the administration of the Plan.  All questions of
interpretation and application of such rules and regulations, of the Plan and of
Options, shall be subject to the determination of the Committee, which shall be
final and binding.  The Plan shall be administered in such a manner as to permit
those Options granted hereunder and specially designated under Section 5 as ISOs
to qualify as incentive stock options as described in Section 422 of the
Internal Revenue Code of 1986, as amended (the "Code").

     For so long as Section 16 of the Securities Exchange Act of 1934, as
amended from time to time (the "Exchange Act"), is applicable to the Company,
each member of the Committee shall be a "non-employee director" or the
equivalent within the meaning of Rule 16b-3 under the Exchange Act, and, for so
long as Section 162(m) of the Code is applicable to the Company, an "outside
director" within the meaning of Section 162 of the Code and the regulations
thereunder.  If, however, the Committee is not comprised of two or more "outside
directors," then, although the Committee may still administer the Plan, the
Compensation Committee of the Board of Directors of American Tower Corporation,
so long as it is the parent of the Company, or such other committee that makes
grants pursuant to the parent's stock option or similar plan, shall make grants
of options or other rights under the Plan (if the Compensation Committee or such
committee consists of two or more members who are "outside directors").


     With respect to persons subject to Section 16 of the Exchange Act
("Insiders"), transactions under the Plan are intended to comply with all
applicable conditions of Rule 16b-3 or its successor under the Exchange Act.  To
the extent any provision of the Plan or action by the Committee fails to so
comply, it shall be deemed to be modified so as to be in compliance with such
Rule, or, if such modification is not possible, it shall be deemed to be null
and void, to the extent permitted by law and deemed advisable by the Committee.

     3. OPTION SHARES

     The stock subject to Options under the Plan shall be shares of Common
Stock, par value $.01 per share (the "Stock").  The total amount of the Stock
with respect to which Options may be granted (the "Option Pool"), shall not
exceed in the aggregate 500,000 shares; provided, however, such aggregate number
of shares shall be subject to adjustment in accordance with the provisions of
Section 17.  If an outstanding Option shall expire for any reason or shall
terminate by reason of the death or severance of employment of the Optionee, the
surrender of any such Option, or any other cause, the shares of Stock allocable
to the unexercised portion of such Option may again be subject to an option
under the Plan. The maximum number of shares of Stock subject to Options that
may be granted to any Optionee in the aggregate in any calendar year shall not
exceed 100,000 shares, subject to adjustment in accordance with the provisions
of Section 17.

     4. AUTHORITY TO GRANT OPTIONS

     The Committee may determine, from time to time, which employees of the
Company or any Affiliate or other persons shall be granted Options under the
Plan, the terms of the Options (including without limitation whether an Option
shall be an ISO or a NQO) and the number of shares which may be purchased under
the Option or Options.  Without limiting the generality of the foregoing, the
Committee may from time to time grant:  (a) to such employees (other than
employees of an Affiliate which is not a corporation) as it shall determine an
Option or Options to buy a stated number of shares of Stock under the terms and
conditions of the Plan which Option or Options will to the extent so designated
at the time of grant constitute an ISO; and (b) to such eligible directors,
employees or other persons as it shall determine an Option or Options to buy a
stated number of shares of Stock under the terms and conditions of the Plan
which Option or Options shall constitute a NQO.  Subject only to any applicable
limitations set forth elsewhere in the Plan, the number of shares of Stock to be
covered by any Option shall be as determined by the Committee.

     5. WRITTEN AGREEMENT

     Each Option granted hereunder shall be embodied in an option agreement (the
"Option Agreement") substantially in the form of Exhibit 1, which shall be
signed by the Optionee and by the Chief Executive Officer, the Chief Operating
Officer, Chief Financial Officer, the General Counsel or the Corporate
Controller of the Company for and in the name and on behalf of the Company.  An
Option Agreement may contain such restrictions on exercisability and such other
provisions not inconsistent with the Plan as the Committee in its sole and
absolute discretion shall approve.

     6. ELIGIBILITY

     The individuals who shall be eligible for grant of Options under the Plan
shall be employees (including officers who may be members of the Board),
directors who are not employees and other individuals, whether or not employees,
who render services of special importance to the management, operation or
development of the Company or an Affiliate, and who have contributed or may be
expected to contribute to the success of the Company or an Affiliate.  An
employee, director or other person to

                                      -2-


whom an Option has been granted pursuant to an Option Agreement is hereinafter
referred to as an "Optionee."

     7. OPTION PRICE

     The price at which shares of Stock may be purchased pursuant to an Option
shall be specified by the Committee at the time the Option is granted, but shall
in no event be less than the par value of such shares and, in the case of an
ISO, except as set forth in the following sentence, one hundred percent (100%)
of the fair market value of the Stock on the date the ISO is granted.  In the
case of an employee who owns (or is considered under Section 424(d) of the Code
as owning) stock possessing more than ten percent (10%) of the total combined
voting power of all classes of stock of the Company or any Affiliate, the price
at which shares of Stock may be so purchased pursuant to an ISO shall be not
less than one hundred and ten percent (110%) of the fair value of the Stock on
the date the ISO is granted.

     For purposes of the Plan, the "fair market value" of a share of Stock on
any date specified herein, shall mean (a) the last reported sales price, regular
way, or, in the event that no sale takes place on such day, the average of the
reported closing bid and asked prices, regular way, in either case (i) as
reported on the New York Stock Exchange Composite Tape, or (ii) if the Stock is
not listed or admitted to trading on the New York Stock Exchange, on the
principal national securities exchange on which such security is listed or
admitted to trading, or (iii) if not then listed or admitted to trading on any
national securities exchange, on the NASDAQ National Market System; or (b) if
the Stock is not quoted on such National Market System, (i) the average of the
closing bid and asked prices on each such day in the over-the-counter market as
reported by NASDAQ, or (ii) if bid and asked prices for such security on each
such day shall not have been reported through NASDAQ, the average of the bid and
asked prices for such day as furnished by any New York Stock Exchange member
firm regularly making a market in such security selected for such purpose by the
Committee; or (c) if the Stock is not then listed or admitted to trading on any
national exchange or quoted in the over-the-counter market, the fair value
thereof determined in good faith by the Committee (which shall be entitled to
take into account that the Stock may be illiquid, may be subject to restrictions
on transfer or may constitute a minority interest in the Company); provided,
however, that any method of determining fair market value employed by the
Committee with respect to an ISO shall be consistent with any applicable laws or
regulations pertaining to "incentive stock options."

     8. DURATION OF OPTIONS

     The duration of any Option shall be specified by the Committee in the
Option Agreement, but no Option shall be exercisable after the expiration of ten
(10) years from the date such Option is granted.  In the case of any employee
who owns (or is considered under Section 424(d) of the Code as owning) stock
possessing more than ten percent (10%) of the total combined voting power of all
classes of stock of the Company or any Affiliate, no ISO shall be exercisable
after the expiration of five (5) years from the date such Option is granted.
The Committee, in its sole and absolute discretion, may extend any Option
theretofore granted.

     9. VESTING PROVISIONS

     Each Option may be exercised so long as it is valid and outstanding from
time to time, in part or as a whole, in such manner and subject to such
conditions as the Committee, in its sole and absolute discretion, may provide in
the Option Agreement.  The Committee may, in its sole and absolute discretion,
accelerate Options, in whole or in part, on such terms and conditions as the
Committee may, in its sole and absolute discretion, determine.

                                      -3-


     10. EXERCISE OF OPTIONS

     Options shall be exercised by the delivery of written notice to the Company
setting forth the number of shares of Stock with respect to which the Option is
to be exercised, accompanied by payment of the option price of such shares,
which payment shall be made, subject to the alternative provisions of this
Section, in cash or by such cash equivalents, payable to the order of the
Company in an amount in United States dollars equal to the option price of such
shares, as the Committee in its sole and absolute discretion shall consider
acceptable.  Such notice shall be delivered in person to the Secretary of the
Company or shall be sent by registered mail, return receipt requested, to the
Secretary of the Company, in which case delivery shall be deemed made on the
date such notice is deposited in the mail.

     Alternatively, if the Option Agreement so specifies, and subject to such
rules as may be established by the Committee, payment of the option price may be
made through a so-called "cashless exercise" procedure, under which the Optionee
shall deliver irrevocable instructions to a broker to sell shares of Stock
acquired upon exercise of the Option and to remit promptly to the Company a
sufficient portion of the sale proceeds to pay the option price and any tax
withholding resulting from such exercise.

     Alternatively, payment of the option price may be made, in whole or in
part, in shares of Stock owned by the Optionee; provided, however, that the
Optionee may not make payment in shares of Stock that he acquired upon the
earlier exercise of any ISO (or other "incentive stock option"), unless and
until he has held the shares until at least two (2) years after the date the ISO
(or such other incentive stock option) was granted and at least one (1) year
after the date the ISO (or such other option) was exercised.  If payment is made
in whole or in part in shares of Stock, then the Optionee shall deliver to the
Company in payment of the option price of the shares with respect of which such
Option is exercised (a) certificates registered in the name of such Optionee
representing a number of shares of Stock legally and beneficially owned by such
Optionee, free of all liens, claims and encumbrances of every kind, and having a
fair market value on the date of delivery of such notice equal to the option
price of the shares of Stock with respect to which such Option is to be
exercised, such certificates to be accompanied by stock powers duly endorsed in
blank by the record holder of the shares of Stock represented by such
certificates; and (b) if the option price of the shares with respect to which
such Option is to be exercised exceeds such fair market value, cash or such cash
equivalents payable to the order to the Company, in an amount in United States
dollars equal to the amount of such excess, as the Committee in its sole and
absolute discretion shall consider acceptable.  Notwithstanding the foregoing
provisions of this Section, the Committee, in its sole and absolute discretion,
(i) may refuse to accept shares of Stock in payment of the option price of the
shares of Stock with respect to which such Option is to be exercised and, in
that event, any certificates representing shares of Stock which were delivered
to the Company with such written notice shall be returned to such Optionee
together with notice by the Company to such Optionee of the refusal of the
Committee to accept such shares of Stock and (ii) may accept, in lieu of actual
delivery of stock certificates, an attestation by the Optionee substantially in
the form attached herewith as Exhibit C or such other form as may be deemed
acceptable by the Committee that he or she owns of record the shares to be
tendered free and clear of all liens, claims and encumbrances of every kind.

     Alternatively, if the Option Agreement so specifies, payment of the option
price may be made in part by a full recourse promissory note executed by the
Optionee and containing the following terms and conditions (and such others as
the Committee shall, in its sole and absolute discretion, determine from time to
time):  (a) it shall be collaterally secured by the shares of Stock obtained
upon exercise of the Option; (b) repayment shall be made on demand by the
Company and, in any event, no later than three (3) years from the date of
exercise; and (c) the note shall bear interest at a rate as determined by the
Committee, payable monthly out of a payroll deduction provision; provided,
however, that notwithstanding the foregoing (i) an amount not less than the par
value of the shares of Stock with respect to which the Option is being exercised
must be paid in cash, cash equivalents, or shares of Stock in accordance with
this Section, and (ii) the payment of such exercise price by promissory note
does not violate any applicable laws or regulations, including, without
limitation, Delaware corporate law or applicable margin lending rules.  The
decision as to whether to permit partial payment by a promissory

                                      -4-


note for shares of Stock to be issued upon exercise of any Option granted shall
rest entirely in the sole and absolute discretion of the Committee.

     As promptly as practicable after the receipt by the Company of (a) written
notice from the Optionee setting forth the number of shares of Stock with
respect to which such Option is to be exercised and (b) payment of the option
price of such shares in the form required by the foregoing provisions of this
Section, the Company shall cause to be delivered to such Optionee certificates
representing the number of shares with respect to which such Option has been so
exercised (less a number of shares equal to the number of shares as to which
ownership was attested under the procedure described in clause (ii) of the next
preceding paragraph).

     11. TRANSFERABILITY OF OPTIONS

     Options shall not be transferable by the Optionee otherwise than by will or
under the laws of descent and distribution, and shall be exercisable during his
or her lifetime only by the Optionee, except that the Committee may, subject to
such conditions as it shall, in its sole and absolute discretion, determine,
specify in an Option Agreement that pertains to an NQO that the Optionee may
transfer such NQO to a member of the Immediate Family of the Optionee, to a
trust solely for the benefit of the Optionee and the Optionee's Immediate
Family, or to a partnership or limited liability company whose only partners or
members are the Optionee and members of the Optionee's Immediate Family.
"Immediate Family" shall mean, with respect to any Optionee, such Optionee's
child, stepchild, grandchild, parent, stepparent, grandparent, spouse, sibling,
mother-in-law, father-in-law, son-in-law, daughter-in-law, brother-in-law, or
sister-in-law, and shall include adoptive relationships.

     12. TERMINATION OF EMPLOYMENT OR INVOLVEMENT OF OPTIONEE WITH THE COMPANY

     For purposes of this Section, employment by or involvement with (in the
case of an Optionee who is not an employee) an Affiliate shall be considered
employment by or involvement with the Company.  Except as otherwise set forth in
the Option Agreement, after the Optionee's termination of employment with the
Company other than by reason of death or disability, including his retirement in
good standing from the employ of the Company for reasons of age under the then
established rules of the Company, the Option shall terminate on the earlier of
the date of its expiration or three (3) months after the date of such
termination or retirement.  After the death of the Optionee, his or her
executors, administrators or any persons to whom his or her Option may be
transferred by will or by the laws of descent and distribution shall have the
right to exercise the Option to the extent to which the Optionee was entitled to
exercise the Option.  The Committee may, subject to such conditions as it shall,
in its sole and absolute discretion, determine, specify in an Option Agreement
that, in the event that such termination is a result of disability, the Optionee
shall have the right to exercise the Option pursuant to its terms as if such
Optionee continued as an employee; provided, however, that any such Option that
is an ISO shall, in order to preserve its status as such, be required to be
exercised with twelve (12) months of such termination.

     Authorized leave of absence or absence on military or government service
shall not constitute severance of the employment relationship between the
Company and the Optionee for purposes of the Plan, provided that either (a) such
absence is for a period of no more than ninety (90) days or (b) the Employee's
right to re-employment after such absence is guaranteed either by statute or by
contract.

     For Optionees who are not employees of the Company, options shall be
exercisable for such periods following the termination of the Optionee's
involvement with the Company as may be set forth in the Option Agreement.

                                      -5-


     13. REQUIREMENTS OF LAW

     The Company shall not be required to sell or issue any shares of Stock upon
the exercise of any Option if the issuance of such shares shall constitute or
result in a violation by the Optionee or the Company of any provisions of any
law, statute or regulation of any governmental authority.  Specifically, in
connection with the Securities Act of 1933, as amended (the "Securities Act"),
and any applicable state securities or "blue sky" law (a "Blue Sky Law"), upon
exercise of any Option the Company shall not be required to issue such shares
unless the Committee has received evidence satisfactory to it to the effect that
the holder of such Option will not transfer such shares except pursuant to a
registration statement in effect under the Securities Act and Blue Sky Laws or
unless an opinion of counsel satisfactory to the Company has been received by
the Company to the effect that such registration and compliance is not required.
Any determination in this connection by the Committee shall be final, binding
and conclusive.  The Company shall not be obligated to take any action in order
to cause the exercise of an Option or the issuance of shares of Stock pursuant
thereto to comply with any law or regulations of any governmental authority,
including, without limitation, the Securities Act or applicable Blue Sky Law.

     Notwithstanding any other provision of the Plan to the contrary, the
Company may refuse to permit transfer of shares of Stock if in the opinion of
its legal counsel such transfer would violate federal or state securities laws
or subject the Company to liability thereunder.  Any sale, assignment, transfer,
pledge or other disposition of shares of Stock received upon exercise of any
Option (or any other shares or securities derived therefrom) which is not in
accordance with the provisions of this Section shall be void and of no effect
and shall not be recognized by the Company.

     Legend on Certificates.  The Committee may cause any certificate
     ----------------------
representing shares of Stock acquired upon exercise of an Option (and any other
shares or securities derived therefrom) to bear a legend to the effect that the
securities represented by such certificate have not been registered under the
Securities Act of 1933, as amended, or any applicable state securities laws, and
may not be sold, assigned, transferred, pledged or otherwise disposed of except
in accordance with the Plan and applicable agreements binding the holder and the
Company or any of its stockholders.

     14. NO RIGHTS AS STOCKHOLDER

     No Optionee shall have any rights as a stockholder with respect to shares
covered by his or her Option until the date of issuance of a stock certificate
for such shares; except as otherwise provided in Section 17, no adjustment for
dividends or otherwise shall be made if the record date therefor is prior to the
date of issuance of such certificate.

     15. EMPLOYMENT OBLIGATION

     The granting of any Option shall not impose upon the Company or any
Affiliate any obligation to employ or continue to employ any Optionee, or to
engage or retain the services of any person, and the right of the Company or any
Affiliate to terminate the employment or services of any person shall not be
diminished or affected by reason of the fact that an Option has been granted to
him or her.  The existence of any Option shall not be taken into account in
determining any damages relating to termination of employment or services for
any reason.

     16. FORFEITURE AS A RESULT OF TERMINATION FOR CAUSE

     Notwithstanding any provision of the Plan to the contrary, if the Committee
determines, after full consideration of the facts presented on behalf of the
Company and an Optionee, that

                                      -6-


          (a)  the Optionee has been engaged in fraud, embezzlement, theft,
     commission of a felony or dishonesty in the course of his or her employment
     by or involvement with the Company or an Affiliate, which damaged the
     Company or an Affiliate, or has made unauthorized disclosure of trade
     secrets or other proprietary information of the Company or an Affiliate or
     of a third party who has entrusted such information to the Company or an
     Affiliate, or

          (b)  the Optionee's employment or involvement was otherwise terminated
     for "cause," as defined in any employment agreement with the Optionee, if
     applicable, or if there is no such agreement, as determined by the
     Committee, which may determine that "cause" includes among other matters
     the willful failure or refusal of the Optionee to perform and carry out his
     or her assigned duties and responsibilities diligently and in a manner
     satisfactory to the Committee, or the material breach by the Optionee of
     any rules of conduct, policies or regulations of the Company or any
     Affiliate,

then the Optionee's right to exercise an Option shall terminate as of the date
of such act (in the case of (a)) or such termination (in the case of (b)) and
the Optionee shall forfeit all unexercised Options.  If an Optionee whose
behavior the Company asserts falls within the provisions of (a) or (b) above has
exercised or attempts to exercise an Option prior to a decision of the
Committee, the Company shall not be required to recognize such exercise until
the Committee has made its decision and, in the event of any exercise shall have
taken place, it shall be of no force and effect (and void ab initio) if the
Committee makes an adverse determination; provided, however, if the Committee
finds in favor of the Optionee then the Optionee will be deemed to have
exercised such Option retroactively as of the date he or she originally gave
written notice of his or her attempt to exercise or actual exercise, as the case
may be.  The decision of the Committee as to the cause of an Optionee's
discharge and the damage done to the Company or an Affiliate shall be final,
binding and conclusive.  No decision of the Committee, however, shall affect in
any manner the finality of the discharge of such Optionee by the Company or an
Affiliate.

     17. CHANGES IN THE COMPANY'S CAPITAL STRUCTURE

     The existence of outstanding Options shall not affect in any way the right
or power of the Company or its stockholders to make or authorize any or all
adjustments, recapitalizations, reorganizations or other changes in the
Company's capital structure or its business or any merger or consolidation of
the Company or any issue of bonds, debentures, preferred or preference stock,
whether or not convertible into the Stock or other securities, ranking prior to
the Stock or affecting the rights thereof, or warrants, rights or options to
acquire the same, or the dissolution or liquidation of the Company or any sale
or transfer of all or any part of its assets or business or any other corporate
act or proceeding, whether of a similar character or otherwise.

     The number of shares of Stock in the Option Pool (less the number of shares
theretofore delivered upon exercise of Options) and the number of shares of
Stock covered by any outstanding Option and the price per share payable upon
exercise thereof (provided that in no event shall the option price be less than
the par value of such shares) shall be proportionately adjusted for any increase
or decrease in the number of issued and outstanding shares of Stock resulting
from any subdivision, split, combination or consolidation of shares of Stock or
the payment of a dividend in shares of stock or other securities of the Company
on the Stock.  The decision of the Board as to the adjustment, if any, required
by the provisions of this Section shall be final, binding and conclusive.

     If the Company merges or consolidates with a wholly-owned subsidiary for
the purpose of reincorporating itself under the laws of another jurisdiction,
the Optionees will be entitled to acquire shares of Stock of the reincorporated
Company upon the same terms and conditions as were in effect immediately prior
to such reincorporation (unless such reincorporation involves a change in the
number of shares or the capitalization of the Company, in which case
proportional adjustments shall be made as

                                      -7-


provided above) and the Plan, unless otherwise rescinded by the Board, will
remain the Plan of the reincorporated Company.

     Except as otherwise provided in the preceding paragraph, if the Company is
merged or consolidated with another corporation, whether or not the Company is
the surviving entity, or if the Company is liquidated or sells or otherwise
disposes of all or substantially all of its assets to another entity while
unexercised Options remain outstanding under the Plan, or if other circumstances
occur in which the Board in its sole and absolute discretion deems it
appropriate for the provisions of this paragraph to apply (in each case, an
"Applicable Event"), then (a) each holder of an outstanding Option shall be
entitled, upon exercise of such Option, to receive in lieu of shares of Stock,
such stock or other securities or property as he or she would have received had
he exercised such option immediately prior to the Applicable Event; (b) the
Board may, in its sole and absolute discretion, waive, generally or in one or
more specific cases, any limitations imposed pursuant to Section 9 so that some
or all Options from and after a date prior to the effective date of such
Applicable Event, specified by the Board, in its sole and absolute discretion,
shall be exercisable in full or in part; (c) the Board may, in its sole and
absolute discretion, cancel all outstanding and unexercised Options as of the
effective date of any such Applicable Event; (d) the Board may, in its sole
discretion, convert some or all Options into options to purchase the stock or
other securities of the surviving corporation pursuant to an Applicable Event;
or (e) the Board may, in its sole and absolute discretion, assume the
outstanding and unexercised options to purchase stock or other securities of any
corporation and convert such options into Options to purchase Stock, whether
pursuant to this Plan or not, pursuant to an Applicable Event; provided,
however, notice of any such cancellation pursuant to clause (c) shall be given
to each holder of an Option not less than thirty (30) days preceding the
effective date of such Applicable Event, and provided further, however, that the
Board may, in its sole and absolute discretion, waive, generally or in one or
more specific instances, any limitations imposed pursuant to Section 9 with
respect to any Option so that such Option shall be exercisable in full or in
part during such thirty (30) day period.

     Except as expressly provided herein, the issue by the Company of shares of
Stock or other securities of any class or series or securities convertible into
or exchangeable or exercisable for shares of Stock or other securities of any
class or series for cash or property or for labor or services either upon direct
sale or upon the exercise of rights or warrants to subscribe therefor, or upon
conversion of shares or obligations of the Company convertible into such shares
or other securities, shall not affect, and no adjustment by reason thereof shall
be made with respect to, the number, class or price of shares of Stock then
subject to outstanding Options.

     18. AMENDMENT OR TERMINATION OF PLAN

     The Board may, in its sole and absolute discretion, modify, revise or
terminate the Plan at any time and from time to time; provided, however, that
without the further approval of the holders of at least a majority of the
outstanding shares of Stock, the Board may not change the aggregate number of
shares of Stock which may be issued under Options pursuant to the provisions of
the Plan either to any one person or in the aggregate, or change the class of
persons eligible to receive ISOs.  Notwithstanding the preceding sentence, the
Board shall in all events have the power and authority to make such changes in
the Plan and in the regulations and administrative provisions hereunder or in
any outstanding Option as, in the opinion of counsel for the Company, may be
necessary or appropriate from time to time to enable any Option granted pursuant
to the Plan to qualify as an incentive stock option or such other stock option
as may be defined under the Code, as amended from time to time, so as to receive
preferential federal income tax treatment.

                                      -8-


     19. CERTAIN RIGHTS OF THE COMPANY

     Voluntary or Involuntary Transfers of Stock.  Except as may be set forth in
     -------------------------------------------
any applicable Optionee/Stockholder Agreement, shares of Stock acquired by an
Optionee pursuant to the exercise of an Option or Options granted under the Plan
shall not be voluntarily transferred by the Optionee without the prior written
consent of the Committee, which consent may be withheld or conditioned as the
Committee, in its sole and absolute discretion, determine.  If such shares of
Stock are subject to an involuntary transfer, including by reason of death, a
divorce settlement or judicial proceeding, the Company shall have the assignable
right to repurchase all or any such shares (including any shares of other
securities of the Company derived therefrom) at a price equal to the Repurchase
Price at the time of the involuntary transfer event.  The Company may exercise
its repurchase right no earlier than one hundred eighty (180) days after the
exercise of the Option (or one or more such exercises) and no later than three
hundred and sixty-five (365) days following the later of (a) the date of such
involuntary transfer of such shares of Stock, and (b) the Committee's receipt of
written notice of the occurrence of such transfer event.  Any such shares of
Stock (or other shares or securities) as to which the Company does not exercise
its repurchase rights within such period shall thereafter be free of the
foregoing restrictions.

     Termination of Employment or Involvement.  If the Optionee's employment by
     ----------------------------------------
or involvement with the Company (including, for this purpose, any Affiliate)
shall terminate for any reason other than the Optionee's death or a Justifiable
Termination (as defined below) or Optionee's retirement for reasons of age or
disability in accordance with the then policy of the Company, the Company shall
have the right to repurchase all or any of such shares of Stock (or other shares
or securities derived therefrom) at a price equal to the Repurchase Price at the
time of such repurchase.  In addition, if at the time of such termination an
Optionee holds an Option granted under the Plan which is by its terms
exercisable after such termination, the Company shall have the assignable right
to repurchase all or any part of the shares of Stock acquired pursuant to the
exercise of such Option, at the Repurchase Price.  In the case of a termination
on account of any circumstance listed in Section 16(a) or (b) (a "Justifiable
Termination"), the Company shall have the right to repurchase all or any of such
shares of Stock at the lesser of (i) the exercise price per share or (ii) the
Repurchase Price at the time of such repurchase.  If the option price for any
repurchased shares has been paid by the Optionee's promissory note pursuant to
Section 10, then the repurchase price for such shares of Stock shall be first
applied to the repayment of the outstanding amount, if any, due under such note
in respect of the repurchased shares, and any accrued but unpaid interest
thereon.   The Company's right to repurchase shares of Stock (or other shares or
securities) may be exercised at any time no later than three hundred and sixty-
five (365) days following the date of the Optionee's termination of employment
or involvement.  Any such shares of Stock (or other shares or securities) as to
which the Company does not exercise its repurchase rights within such period
shall thereafter be free of the foregoing restrictions.

     Repurchase Price.  As used herein the term "Repurchase Price" shall mean
     ----------------
the fair market value of a share of Stock (or other shares or securities) as
determined in accordance with the provisions of Section 7, except that in making
its determination of fair market value of a share of Stock the Committee shall
be entitled to take into account that the shares of Stock (or other shares and
securities) may be illiquid, may be subject to restrictions on transfer or may
constitute a minority interest in the Company.

     Stockholder Agreement.  Unless the Committee shall, in its sole and
     ---------------------
absolute discretion otherwise determine, it shall be a condition of each
Optionee receiving any shares of Stock upon any exercise of an Option that he or
she shall enter into the Optionee/Stockholder Agreement, a copy of which has
heretofore been delivered to the Optionee.

     Other Provisions.  The Committee may, in its sole and absolute discretion,
     ----------------
require a key employee, as a condition to receiving any option, to enter into a
noncompetition agreement in such form as the Committee may, from time to time in
its sole and absolute discretion, determine.

                                      -9-


     20. GOVERNING LAW

     The Plan shall be governed by and construed and enforced in accordance with
the applicable laws of the United States of America and the law (other than the
law governing conflict of law questions) of The Commonwealth of Massachusetts
except to the extent the laws of any other jurisdiction are mandatorily
applicable.

     21. EFFECTIVE DATE AND DURATION OF THE PLAN

     The Plan shall become effective and shall be deemed to have been adopted on
March 28, 2000.  Unless the Plan shall have terminated earlier, the Plan shall
terminate on the tenth (10th) anniversary of its effective date, and no Option
shall be granted pursuant to the Plan after the day preceding the tenth (10th)
anniversary of its effective date.

                                      -10-



                                                                         Annex D




================================================================================


                      AMERICAN TOWER SYSTEMS CORPORATION

                            1997 Stock Option Plan
                   As Amended and Restated on April 27, 1998


================================================================================


                      AMERICAN TOWER SYSTEMS CORPORATION
                            1997 STOCK OPTION PLAN

                               TABLE OF CONTENTS



                                                                            Page
                                                                            ----
                                                                         
1.  PURPOSE................................................................    1
2.  ADMINISTRATION OF THE PLAN.............................................    1
3.  OPTION SHARES..........................................................    2
4.  AUTHORITY TO GRANT OPTIONS.............................................    2
5.  WRITTEN AGREEMENT......................................................    2
6.  ELIGIBILITY............................................................    3
7.  OPTION PRICE...........................................................    3
8.  DURATION OF OPTIONS....................................................    4
9.  VESTING PROVISIONS.....................................................    4
10.  EXERCISE OF OPTIONS...................................................    4
11.  TRANSFERABILITY OF OPTIONS............................................    5
12.  TERMINATION OF EMPLOYMENT OR INVOLVEMENT OF OPTIONEE
         WITH THE COMPANY..................................................    6
13.  REQUIREMENTS OF LAW...................................................    6
14.  NO RIGHTS AS STOCKHOLDER..............................................    7
15.  EMPLOYMENT OBLIGATION.................................................    7
16.  FORFEITURE AS A RESULT OF TERMINATION FOR CAUSE.......................    7
17.  CHANGES IN THE COMPANY'S CAPITAL STRUCTURE............................    8
18.  AMENDMENT OR TERMINATION OF PLAN......................................    9
19.  EFFECTIVE DATE AND DURATION OF THE PLAN...............................   10


                                       i


                      AMERICAN TOWER SYSTEMS CORPORATION

                            1997 STOCK OPTION PLAN

     1.   PURPOSE

     The purpose of this 1997 Stock Option Plan (the "Plan") is to encourage
directors, consultants and employees of American Tower Systems Corporation (the
"Company") and its Subsidiaries (as hereinafter defined) to continue their
association with the Company and its Subsidiaries, by providing opportunities
for such persons to participate in the ownership of the Company and in its
future growth through the granting of stock options (the "Options") which may be
options designed to qualify as incentive stock options (within the meaning of
Section 422 of the Internal Revenue Code of 1986, as amended (the "Code") (an
"ISO"), or options not intended to qualify for any special tax treatment under
the Code (a "NQO"). The term "Subsidiary" as used in the Plan means a
corporation or other business organization of which the Company owns, directly
or indirectly through an unbroken chain of ownership, fifty percent (50%) or
more of the total combined voting power of all classes of stock.

     2.   ADMINISTRATION OF THE PLAN

     The Plan shall be administered by a committee (the "Committee") consisting
of two or more members of the Company's Board of Directors (the "Board"). The
Committee shall from time to time determine to whom options or other rights
shall be granted under the Plan, whether options granted shall be incentive
stock options ("ISOs") or nonqualified stock options ("NSOs"), the terms of the
options or other rights, and the number of shares that may be granted under
options. The Committee shall report to the Board the names of individuals to
whom stock or options or other rights are to be granted, the number of shares
covered, and the terms and conditions of each grant. The determinations
described in this Section 2 may be made by the Committee or by the Board, as the
Board shall direct in its discretion, and references in the Plan to the
Committee shall be understood to refer to the Board in any such case.

     The Committee shall select one of its members as Chairman and shall hold
meetings at such times and places as it may determine. A majority of the
Committee shall constitute a quorum, and acts of the Committee at which a quorum
is present, or acts reduced to or approved in writing by all the members of the
Committee, shall be the valid acts of the Committee. The Committee shall have
the authority to adopt, amend, and rescind such rules and regulations as, in its
opinion, may be advisable in the administration of the Plan. All questions of
interpretation and application of such rules and regulations, of the Plan and of
options granted thereunder (the "Options"), shall be subject to the
determination of the Committee, which shall be final and binding. The Plan shall
be administered in such a manner as to permit those Options granted hereunder
and specially designated under Section 5 hereof as an ISO to qualify as
incentive stock options as described in Section 422 of the Internal Revenue Code
of 1986, as amended (the "Code").

     For so long as Section 16 of the Securities Exchange Act of 1934, as
amended from time to time (the "Exchange Act"), is applicable to the Company,
each member of the Committee


shall be a "non-employee director" or the equivalent within the meaning of Rule
16b-3 under the Exchange Act, and, for so long as Section 162(m) of the Code is
applicable to the Company, an "outside director" within the meaning of Section
162 of the Code and the regulations thereunder.

     With respect to persons subject to Section 16 of the Exchange Act
("Insiders"), transactions under the Plan are intended to comply with all
applicable conditions of Rule 16b-3 or its successor under the Exchange Act. To
the extent any provision of the Plan or action by the Committee fails to so
comply, it shall be deemed to be modified so as to be in compliance with such
Rule, or, if such modification is not possible, it shall be deemed to be null
and void, to the extent permitted by law and deemed advisable by the Committee.

     3.   OPTION SHARES

     The stock subject to Options under the Plan shall be shares of Class A and
Class B Common Stock, par value $.01 per share (the "Stock"), provided, however,
                                                              --------  -------
that after the consummation of the ATC Merger as defined in the Agreement and
Plan of Merger by and between the Company and American Tower Corporation, dated
December 12, 1997, as may be amended, any Options granted shall be for shares of
Class A. The total amount of the Stock with respect to which Options may be
granted (the "Option Pool"), shall not exceed in the aggregate 24,000,000/1/
shares; provided, however, such aggregate number of shares shall be subject to
adjustment in accordance with the provisions of Section 17. In the event that
any outstanding Option shall expire for any reason or shall terminate by reason
of the death or severance of employment of the Optionee, the surrender of any
such Option, or any other cause, the shares of Stock allocable to the
unexercised portion of such Option may again be subject to an option under the
Plan. The maximum number of shares of Stock subject to Options that may be
granted to any Optionee in the aggregate in any calendar year shall not exceed
5,000,000 shares.

     4.   AUTHORITY TO GRANT OPTIONS

     The Committee may determine, from time to time, which employees of the
Company or any Subsidiary or other persons shall be granted Options under the
Plan, the terms of the Options (including without limitation whether an Option
shall be an ISO or a NQO) and the number of shares which may be purchased under
the Option or Options. Without limiting the generality of the foregoing, the
Committee may from time to time grant: (a) to such employees (other than
employees of a Subsidiary which is not a corporation) as it shall determine an
Option or Options to buy a stated number of shares of Stock under the terms and
conditions of the Plan which Option or Options will to the extent so designated
at the time of grant constitute an ISO; and (b) to such eligible directors,
employees or other persons as it shall determine an Option or Options to buy a
stated number of shares of Stock under the terms and conditions of the Plan
which Option or Options shall constitute a NQO. Subject only to any applicable
limitations set forth elsewhere in the Plan, the number of shares of Stock to be
covered by any Option shall be as determined by the Committee.

     5.   WRITTEN AGREEMENT

_______________________
     /1/ The increase of authorized shares under the Plan was approved by the
Board of Directors on March 9, 2000 and is subject to shareholder approval at
the Annual Meeting to be held on May 18, 2000.

                                      -2-


     Each Option granted hereunder shall be embodied in an option agreement (the
"Option Agreement") substantially in the form of Exhibit 1, which shall be
signed by the Optionee and by the Chief Executive Officer, Chief Financial
Officer or the Corporate Controller of the Company for and in the name and on
behalf of the Company. An Option Agreement may contain such restrictions on
exercisability and such other provisions not inconsistent with the Plan as the
Committee in its sole and absolute discretion shall approve.

     6.   ELIGIBILITY

     The individuals who shall be eligible for grant of Options under the Plan
shall be employees (including officers who may be members of the Board),
directors who are not employees and other individuals, whether or not employees,
who render services of special importance to the management, operation, or
development of the Company or a Subsidiary, and who have contributed or may be
expected to contribute materially to the success of the Company or a Subsidiary.
An employee, director or other person to whom an Option has been granted
pursuant to an Option Agreement is hereinafter referred to as an "Optionee."

     7.   OPTION PRICE

     The price at which shares of Stock may be purchased pursuant to an Option
shall be specified by the Committee at the time the Option is granted, but shall
in no event be less than the par value of such shares and, in the case of an
ISO, except as set forth in the following sentence, one hundred percent (100%)
of the fair market value of the Stock on the date the ISO is granted. In the
case of an employee who owns (or is considered under Section 424(d) of the Code
as owning) stock possessing more than ten percent (10%) of the total combined
voting power of all classes of stock of the Company or any Subsidiary, the price
which shares of Stock may be so purchased pursuant to an ISO shall be not less
than one hundred and ten percent (110%) of the fair value of the Stock on the
date the ISO is granted.

     For purposes of the Plan, the "fair market value" of a share of Stock on
any date specified herein, shall mean (a) the last reported sales price, regular
way, or, in the event that no sale takes place on such day, the average of the
reported closing bid and asked prices, regular way, in either case (i) as
reported on the New York Stock Exchange Composite Tape, or (ii) if the Stock is
not listed or admitted to trading on the New York Stock Exchange, on the
principal national securities exchange on which such security is listed or
admitted to trading, or (iii) if not then listed or admitted to trading on any
national securities exchange, on the NASDAQ National Market System; or (b) if
the Stock is not quoted on such National Market System, (i) the average of the
closing bid and asked prices on each such day in the over-the-counter market as
reported by NASDAQ, or (ii) if bid and asked prices for such security on each
such day shall not have been reported through NASDAQ, the average of the bid and
asked prices for such day as furnished by any New York Stock Exchange member
firm regularly making a market in such security selected for such purpose by the
Committee; or (c) if the Stock is not then listed or admitted to trading on any
national exchange or quoted in the over-the-counter market, the fair value
thereof determined in good faith by the Committee as of a date which is within
thirty (30) days of the date with respect to which the determination is to be
made; provided, however, that any method of determining fair market value
employed by the Committee with respect to an ISO

                                      -3-


shall be consistent with any applicable laws or regulations pertaining to
"incentive stock options."

     8.   DURATION OF OPTIONS

     The duration of any Option shall be specified by the Committee in the
Option Agreement, but no ISO shall be exercisable after the expiration of ten
(10) years, and no NQO shall be exercisable after the expiration of ten (10)
years and one (1) day, from the date such Option is granted. In the case of any
employee who owns (or is considered under Section 424(d) of the Code as owning)
stock possessing more than ten percent (10%) of the total combined voting power
of all classes of stock of the Company or any Subsidiary, no ISO shall be
exercisable after the expiration of five (5) years from the date such Option is
granted. The Committee, in its sole and absolute discretion, may extend any
Option theretofore granted subject to the aforesaid limits and may provide that
an Option shall be exercisable during its entire duration or during any lesser
period of time.

     9.   VESTING PROVISIONS

     Each Option may be exercised so long as it is valid and outstanding from
time to time, in part or as a whole, in such manner and subject to such
conditions as the Committee, in its sole and absolute discretion, may provide in
the Option Agreement.

     10.  EXERCISE OF OPTIONS

     Options shall be exercised by the delivery of written notice to the Company
setting forth the number of shares of Stock with respect to which the Option is
to be exercised, accompanied by payment of the option price of such shares,
which payment shall be made, subject to the alternative provisions of this
Section, in cash or by such cash equivalents, payable to the order of the
Company in an amount in United States dollars equal to the option price of such
shares, as the Committee in its sole and absolute discretion shall consider
acceptable. Such notice shall be delivered in person to the Secretary of the
Company or shall be sent by registered mail, return receipt requested, to the
Secretary of the Company, in which case delivery shall be deemed made on the
date such notice is deposited in the mail.

     Alternatively, if the Option Agreement so specifies, and subject to such
rules as may be established by the Committee, payment of the option price may be
made through a so-called "cashless exercise" procedure, under which the Optionee
shall deliver irrevocable instructions to a broker to sell shares of Stock
acquired upon exercise of the Option and to remit promptly to the Company a
sufficient portion of the sale proceeds to pay the option price and any tax
withholding resulting from such exercise.

     Alternatively, payment of the option price may be made, in whole or in
part, in shares of Stock owned by the Optionee; provided, however, that the
Optionee may not make payment in shares of Stock that he acquired upon the
earlier exercise of any ISO (or other "incentive stock option"), unless and
until he has held the shares until at least two (2) years after the date the ISO
(or such other incentive stock option) was granted and at least one (1) year
after the date the ISO (or such other option) was exercised. If payment is made
in whole or in part in shares of Stock,

                                      -4-


then the Optionee shall deliver to the Company in payment of the option price of
the shares with respect of which such Option is exercised (a) certificates
registered in the name of such Optionee representing a number of shares of Stock
legally and beneficially owned by such Optionee, free of all liens, claims and
encumbrances of every kind, and having a fair market value on the date of
delivery of such notice equal to the option price of the shares of Stock with
respect to which such Option is to be exercised, such certificates to be
accompanied by stock powers duly endorsed in blank by the record holder of the
shares of Stock represented by such certificates; and (b) if the option price of
the shares with respect to which such Option is to be exercised exceeds such
fair market value, cash or such cash equivalents payable to the order to the
Company, in an amount in United States dollars equal to the amount of such
excess, as the Committee in its sole and absolute discretion shall consider
acceptable. Notwithstanding the foregoing provisions of this Section, the
Committee, in its sole and absolute discretion (i) may refuse to accept shares
of Stock in payment of the option price of the shares of Stock with respect to
which such Option is to be exercised and, in that event, any certificates
representing shares of Stock which were delivered to the Company with such
written notice shall be returned to such Optionee together with notice by the
Company to such Optionee of the refusal of the Committee to accept such shares
of Stock and (ii) may accept, in lieu of actual delivery of stock certificates,
an attestation by the Optionee substantially in the form attached herewith as
Exhibit C or such other form as may be deemed acceptable by the Committee that
he or she owns of record the shares to be tendered free and clear of all liens,
claims and encumbrances of every kind.

     Alternatively, if the Option Agreement so specifies, payment of the option
price may be made in part by a promissory note executed by the Optionee and
containing the following terms and conditions (and such others as the Committee
shall, in its sole and absolute discretion determine from time to time): (a) it
shall be collaterally secured by the shares of Stock obtained upon exercise of
the Option; (b) repayment shall be made on demand by the Company and, in any
event, no later than three (3) years from the date of exercise; and (c) the note
shall bear interest at a rate as determined by the Committee, payable monthly
out of a payroll deduction provision; provided, however, that notwithstanding
the foregoing (i) an amount not less than the par value of the shares of Stock
with respect to which the Option is being exercised must be paid in cash, cash
equivalents, or shares of Stock in accordance with this Section, and (ii) the
payment of such exercise price by promissory note does not violate any
applicable laws or regulations, including, without limitation, Delaware
corporate law or applicable margin lending rules. The decision as to whether to
permit partial payment by a promissory note for shares of Stock to be issued
upon exercise of any Option granted shall rest entirely in the sole and absolute
discretion of the Committee.

     As promptly as practicable after the receipt by the Company of (a) written
notice from the Optionee setting forth the number of shares of Stock with
respect to which such Option is to be exercised and (b) payment of the option
price of such shares in the form required by the foregoing provisions of this
Section, the Company shall cause to be delivered to such Optionee certificates
representing the number of shares with respect to which such Option has been so
exercised (less a number of shares equal to the number of shares as to which
ownership was attested under the procedure described in clause (ii) of the next
preceding paragraph).

     11.  TRANSFERABILITY OF OPTIONS

                                      -5-


     Options shall not be transferable by the Optionee otherwise than by will or
under the laws of descent and distribution, and shall be exercisable during his
or her lifetime only by the Optionee, except that the Committee may specify in
an Option Agreement that pertains to an NQO that the Optionee may transfer such
NQO to a member of the Immediate Family of the Optionee, to a trust solely for
the benefit of the Optionee and the Optionee's Immediate Family, or to a
partnership or limited liability company whose only partners or members are the
Optionee and members of the Optionee's Immediate Family. "Immediate Family"
shall mean, with respect to any Optionee, such Optionee's child, stepchild,
grandchild, parent, stepparent, grandparent, spouse, sibling, mother-in-law,
father-in-law, son-in-law, daughter-in-law, brother-in-law, or sister-in-law,
and shall include adoptive relationships.

     12.  TERMINATION OF EMPLOYMENT OR INVOLVEMENT OF OPTIONEE WITH THE COMPANY

     For purposes of this Section, employment by or involvement with (in the
case of an Optionee who is not an employee) a Subsidiary shall be considered
employment by or involvement with the Company. Except as otherwise set forth in
the Option Agreement, after the Optionee's termination of employment with the
Company other than by reason of death or disability, including his retirement in
good standing from the employ of the Company for reasons of age under the then
established rules of the Company, the Option shall terminate on the earlier of
the date of its expiration or three (3) months after the date of such
termination or retirement. After the death of the Optionee, his or her
executors, administrators or any persons to whom his or her Option may be
transferred by will or by the laws of descent and distribution shall have the
right to exercise the Option to the extent to which the Optionee was entitled to
exercise the Option. In the event that such termination is a result of
disability, the Optionee shall have the right to exercise the Option pursuant to
its terms as if such Optionee continued as an employee.

     Authorized leave of absence or absence on military or government service
shall not constitute severance of the employment relationship between the
Company and the Optionee for purposes of the Plan, provided that either (a) such
absence is for a period of no more than ninety (90) days or (b) the Employee's
right to re-employment after such absence is guaranteed either by statute or by
contract.

     For Optionees who are not employees of the Company, options shall be
exercisable for such periods following the termination of the Optionee's
involvement with the Company as may be set forth in the Option Agreement.

     13.  REQUIREMENTS OF LAW

     The Company shall not be required to sell or issue any shares of Stock upon
the exercise of any Option if the issuance of such shares shall constitute or
result in a violation by the Optionee or the Company of any provisions of any
law, statute or regulation of any governmental authority. Specifically, in
connection with the Securities Act of 1933, as amended (the "Securities Act"),
and any applicable state securities or "blue sky" law (a "Blue Sky Law"), upon
exercise of any Option the Company shall not be required to issue such shares
unless the Committee has received evidence satisfactory to it to the effect that
the holder of such Option will not transfer such shares except pursuant to a
registration statement in effect under the

                                      -6-


Securities Act and Blue Sky Laws or unless an opinion of counsel satisfactory to
the Company has been received by the Company to the effect that such
registration and compliance is not required. Any determination in this
connection by the Committee shall be final, binding and conclusive. The Company
shall not be obligated to take any action in order to cause the exercise of an
Option or the issuance of shares of Stock pursuant thereto to comply with any
law or regulations of any governmental authority, including, without limitation,
the Securities Act or applicable Blue Sky Law.

     Notwithstanding any other provision of the Plan to the contrary, the
Company may refuse to permit transfer of shares of Stock if in the opinion of
its legal counsel such transfer would violate federal or state securities laws
or subject the Company to liability thereunder. Any sale, assignment, transfer,
pledge or other disposition of shares of Stock received upon exercise of any
Option (or any other shares or securities derived therefrom) which is not in
accordance with the provisions of this Section shall be void and of no effect
and shall not be recognized by the Company.

     Legend on Certificates. The Committee may cause any certificate
     ----------------------
representing shares of Stock acquired upon exercise of an Option (and any other
shares or securities derived therefrom) to bear a legend to the effect that the
securities represented by such certificate have not been registered under the
Federal Securities Act of 1933, as amended, or any applicable state securities
laws, and may not be sold, assigned, transferred, pledged or otherwise disposed
of except in accordance with the Plan and applicable agreements binding the
holder and the Company or any of its stockholders.

     14.  NO RIGHTS AS STOCKHOLDER

     No Optionee shall have any rights as a stockholder with respect to shares
covered by his or her Option until the date of issuance of a stock certificate
for such shares; except as otherwise provided in Section 17, no adjustment for
dividends or otherwise shall be made if the record date therefor is prior to the
date of issuance of such certificate.

     15.  EMPLOYMENT OBLIGATION

     The granting of any Option shall not impose upon the Company or any
Subsidiary any obligation to employ or continue to employ any Optionee, or to
engage or retain the services of any person, and the right of the Company or any
Subsidiary to terminate the employment or services of any person shall not be
diminished or affected by reason of the fact that an Option has been granted to
him or her. The existence of any Option shall not be taken into account in
determining any damages relating to termination of employment or services for
any reason.

     16.  FORFEITURE AS A RESULT OF TERMINATION FOR CAUSE

     Notwithstanding any provision of the Plan to the contrary, if the Committee
determines, after full consideration of the facts presented on behalf of the
Company and an Optionee, that

          (a)  the Optionee has been engaged in fraud, embezzlement, theft,
     commission of a felony or dishonesty in the course of his or her employment
     by or involvement with the Company or a Subsidiary, which damaged the
     Company or a Subsidiary, or has made

                                      -7-


     unauthorized disclosure of trade secrets or other proprietary information
     of the Company or a Subsidiary or of a third party who has entrusted such
     information to the Company or a Subsidiary, or

          (b)  the Optionee's employment or involvement was otherwise terminated
     for "cause," as defined in any employment agreement with the Optionee, if
     applicable, or if there is no such agreement, as determined by the
     Committee, which may determine that "cause" includes among other matters
     the willful failure or refusal of the Optionee to perform and carry out his
     or her assigned duties and responsibilities diligently and in a manner
     satisfactory to the Committee,

then the Optionee's right to exercise an Option shall terminate as of the date
of such act (in the case of (a)) or such termination (in the case of (b)) and
the Optionee shall forfeit all unexercised Options.  If an Optionee whose
behavior the Company asserts falls within the provisions of (a) or (b) above has
exercised or attempts to exercise an Option prior to a decision of the
Committee, the Company shall not be required to recognize such exercise until
the Committee has made its decision and, in the event of any exercise shall have
taken place, it shall be of no force and effect (and void ab initio) if the
                                                          -- ------
Committee makes an adverse determination; provided, however, if the Committee
finds in favor of the Optionee then the Optionee will be deemed to have
exercised such Option retroactively as of the date he or she originally gave
written notice of his or her attempt to exercise or actual exercise, as the case
may be.  The decision of the Committee as to the cause of an Optionee's
discharge and the damage done to the Company or a Subsidiary shall be final,
binding and conclusive.  No decision of the Committee, however, shall affect in
any manner the finality of the discharge of such Optionee by the Company or a
Subsidiary.

     17.  CHANGES IN THE COMPANY'S CAPITAL STRUCTURE

     The existence of outstanding Options shall not affect in any way the right
or power of the Company or its stockholders to make or authorize any or all
adjustments, recapitalizations, reorganizations or other changes in the
Company's capital structure or its business or any merger or consolidation of
the Company or any issue of bonds, debentures, preferred or preference stock,
whether or not convertible into the Stock or other securities, ranking prior to
the Stock or affecting the rights thereof, or warrants, rights or options to
acquire the same, or the dissolution or liquidation of the Company or any sale
or transfer of all or any part of its assets or business or any other corporate
act or proceeding, whether of a similar character or otherwise.

     The number of shares of Stock in the Option Pool (less the number of shares
theretofore delivered upon exercise of Options) and the number of shares of
Stock covered by any outstanding Option and the price per share payable upon
exercise thereof (provided that in no event shall the option price be less than
the par value of such shares) shall be proportionately adjusted for any increase
or decrease in the number of issued and outstanding shares of Stock resulting
from any subdivision, split, combination or consolidation of shares of Stock or
the payment of a dividend in shares of stock or other securities of the Company
on the Stock. The decision of the Board as to the adjustment, if any, required
by the provisions of this Section shall be final, binding and conclusive.

                                      -8-


     If the Company merges or consolidates with a wholly-owned subsidiary for
the purpose of reincorporating itself under the laws of another jurisdiction,
the Optionees will be entitled to acquire shares of Stock of the reincorporated
Company upon the same terms and conditions as were in effect immediately prior
to such reincorporation (unless such reincorporation involves a change in the
number of shares or the capitalization of the Company, in which case
proportional adjustments shall be made as provided above) and the Plan, unless
otherwise rescinded by the Board, will remain the Plan of the reincorporated
Company.

     Except as otherwise provided in the preceding paragraph, if the Company is
merged or consolidated with another corporation, whether or not the Company is
the surviving entity, or if the Company is liquidated or sells or otherwise
disposes of all or substantially all of its assets to another entity while
unexercised Options remain outstanding under the Plan, or if other circumstances
occur in which the Board in its sole and absolute discretion deems it
appropriate for the provisions of this paragraph to apply (in each case, an
"Applicable Event"), then (a) each holder of an outstanding Option shall be
entitled, upon exercise of such Option, to receive in lieu of shares of Stock,
such stock or other securities or property as he or she would have received had
he exercised such option immediately prior to the Applicable Event; or (b) the
Board may, in its sole and absolute discretion, waive, generally or in one or
more specific cases, any limitations imposed pursuant to Section 9 so that some
or all Options from and after a date prior to the effective date of such
Applicable Event, specified by the Board, in its sole and absolute discretion,
shall be exercisable in full; or (c) the Board may, in its sole and absolute
discretion, cancel all outstanding and unexercised Options as of the effective
date of any such Applicable Event; or (d) the Board may, in its sole discretion,
convert some or all Options into options to purchase the stock or other
securities of the surviving corporation pursuant to an Applicable Event; or (e)
the Board may, in its sole and absolute discretion, assume the outstanding and
unexercised options to purchase stock or other securities of any corporation and
convert such options into Options to purchase Stock, whether pursuant to this
Plan or not, pursuant to an Applicable Event; provided, however, notice of any
such cancellation pursuant to clause (c) shall be given to each holder of an
Option not less than thirty (30) days preceding the effective date of such
Applicable Event, and provided further, however, that the Board may, in its sole
and absolute discretion, waive, generally or in one or more specific instances,
any limitations imposed pursuant to Section 9 with respect to any Option so that
such Option shall be exercisable in full or in part, as the Board may, in its
sole and absolute discretion, determine, during such thirty (30) day period.

     Except as expressly provided herein, the issue by the Company of shares of
Stock or other securities of any class or series or securities convertible into
or exchangeable or exercisable for shares of Stock or other securities of any
class or series for cash or property or for labor or services either upon direct
sale or upon the exercise of rights or warrants to subscribe therefor, or upon
conversion of shares or obligations of the Company convertible into such shares
or other securities, shall not affect, and no adjustment by reason thereof shall
be made with respect to, the number, class or price of shares of Stock then
subject to outstanding Options.

     18.  AMENDMENT OR TERMINATION OF PLAN

     The Board may, in its sole and absolute discretion, modify, revise or
terminate the Plan at any time and from time to time; provided, however, that
without the further approval of the

                                      -9-


holders of at least a majority of the outstanding shares of Stock, the Board may
not (a) materially increase the benefits accruing to Optionees under the Plan or
make any "modifications" as that term is defined under Section 424(h)(3) (or its
successor) of the Code if such increase in benefits or modifications would
adversely affect (i) the availability to the Plan of the protections of Section
16(b) of the Exchange Act, if applicable to the Company, or (ii) the
qualification of the Plan or any Options for "incentive stock option" treatment
under Section 422 of the Code; (b) change the aggregate number of shares of
Stock which may be issued under Options pursuant to the provisions of the Plan
either to any one employee or in the aggregate; or (c) change the class of
persons eligible to receive ISOs. Notwithstanding the preceding sentence, the
Board shall in all events have the power and authority to make such changes in
the Plan and in the regulations and administrative provisions hereunder or in
any outstanding Option as, in the opinion of counsel for the Company, may be
necessary or appropriate from time to time to enable any Option granted pursuant
to the Plan to qualify as an incentive stock option or such other stock option
as may be defined under the Code, as amended from time to time, so as to receive
preferential federal income tax treatment.

     19.  EFFECTIVE DATE AND DURATION OF THE PLAN

     The Plan shall become effective and shall be deemed to have been adopted on
November 5, 1997, unless the Plan shall have terminated earlier, the Plan shall
terminate on the tenth (10th) anniversary of its effective date, and no Option
shall be granted pursuant to the Plan after the day preceding the tenth (10th)
anniversary of its effective date.

                                      -10-


PROXY                       AMERICAN TOWER CORPORATION                     PROXY
CLASS A                                                                  CLASS A

                              116 HUNTINGTON AVENUE
                           BOSTON, MASSACHUSETTS 02116

           THIS PROXY IS SOLICITED ON BEHALF OF THE BOARD OF DIRECTORS

The undersigned hereby appoints STEVEN B. DODGE, JOSEPH L. WINN and JONATHAN R.
BLACK, and each of them, as Proxies of the undersigned, each with the power to
appoint his substitute, and hereby authorizes a majority of them, or any one if
only one be present, to represent and to vote, as designated below and on the
reverse hereof, all the Class A Common Stock, $.01 par value per share, of
American Tower Corporation held of record by the undersigned or with respect to
which the undersigned is entitled to vote or act at the 2000 Annual Meeting of
Stockholders to be held on May 18, 2000 or any adjournments thereof.

THIS PROXY WHEN PROPERLY EXECUTED WILL BE VOTED IN THE MANNER DIRECTED HEREIN BY
THE UNDERSIGNED STOCKHOLDER(S). IF NO DIRECTIONS ARE MADE, THE PROXIES WILL VOTE
FOR EACH OF THE MATTERS LISTED ON THE REVERSE SIDE OF THIS CARD AND, AT THEIR
DISCRETION, ON ANY OTHER MATTER THAT MAY PROPERLY COME BEFORE THE MEETING.

               PLEASE VOTE, SIGN, DATE AND RETURN THIS PROXY CARD
                      PROMPTLY USING THE ENCLOSED ENVELOPE.

                  (Continued and to be signed on reverse side.)

                           AMERICAN TOWER CORPORATION
     PLEASE MARK VOTE IN OVAL IN THE FOLLOWING MANNER USING DARK INK ONLY.




                                                                    
1.  Election of Directors
Nominees:  Alan L. Box,  Arnold L. Chavkin,          For      Withhold                For All
Steven B. Dodge, Dean H. Eisner,                     All       For All       (except as written below)
Jack D. Furst, J. Michael Gearon, Jr,
Fred R. Lummis, Randall T. Mays,                     [_]         [_]                    [_]
Thomas H. Stoner and Maggie Wilderotter.


Withheld for the following (write the nominee's name(s) in the space below):

- ----------------------------------------------
- ----------------------------------------------
- ----------------------------------------------

2.  To approve an amendment to
the Company's 1997 Stock Option                   For      Against      Abstain
Plan to increase the number of shares
for which options may be granted from             [_]        [_]          [_]
15,000,000 to 24,000,000.

3.  To approve the adoption of the                For      Against      Abstain
ATC Teleports, Inc. 1999
Stock Option Plan.                                [_]        [_]          [_]


4.  To approve the adoption of the Kline             For     Against     Abstain
Iron & Steel Co., Inc. 2000 Stock Option Plan.

                                                     [_]       [_]         [_]

5.  To approve the adoption of the American          For     Against     Abstain
Tower Corporation 2000 Employee Stock
Purchase Plan.                                       [_]       [_]         [_]


6. Ratification of Deloitte & Touche LLP as          For     Against     Abstain
independent auditors for 2000.
                                                     [_]       [_]         [_]




Dated:____________________, 2000                     Signature(s)______________



                                  NOTE: Please sign exactly as name appears
                                        hereon. Joint owners should each sign.
                                        When signing as attorney, executor,
                                        administrator, trustee or guardian,
                                        please give full title as such. If a
                                        corporation, please sign in full company
                                        name by an authorized officer or if a
                                        partnership please sign in partnership
                                        name by an authorized person.


                                      -2-


PROXY                       AMERICAN TOWER CORPORATION                     PROXY
CLASS B                                                                  CLASS B
                              116 HUNTINGTON AVENUE
                           BOSTON, MASSACHUSETTS 02116

           THIS PROXY IS SOLICITED ON BEHALF OF THE BOARD OF DIRECTORS

          The undersigned hereby appoints STEVEN B. DODGE, JOSEPH L. WINN and
JONATHAN R. BLACK, and each of them, as Proxies of the undersigned, each with
the power to appoint his substitute, and hereby authorizes a majority of them,
or any one if only one be present, to represent and to vote, as designated below
and on the reverse hereof, all the Class B Common Stock, $.01 par value per
share, of American Tower Corporation held of record by the undersigned or with
respect to which the undersigned is entitled to vote or act at the 2000 Annual
Meeting of Stockholders to be held on May 18, 2000 or any adjournments thereof.

THIS PROXY WHEN PROPERLY EXECUTED WILL BE VOTED IN THE MANNER DIRECTED HEREIN BY
THE UNDERSIGNED STOCKHOLDER(S). IF NO DIRECTIONS ARE MADE, THE PROXIES WILL VOTE
FOR EACH OF THE MATTERS LISTED ON THE REVERSE SIDE OF THIS CARD AND, AT THEIR
DISCRETION, ON ANY OTHER MATTER THAT MAY PROPERLY COME BEFORE THE MEETING.

               PLEASE VOTE, SIGN, DATE AND RETURN THIS PROXY CARD
                      PROMPTLY USING THE ENCLOSED ENVELOPE.

                  (Continued and to be signed on reverse side.)

                           AMERICAN TOWER CORPORATION
     PLEASE MARK VOTE IN OVAL IN THE FOLLOWING MANNER USING DARK INK ONLY.



                                                         
1.  Election of Directors--
Nominees:  Alan L. Box, Arnold L. Chavkin,     For   Withhold             For All
Steven B. Dodge, Dean H. Eisner,               All   For All      (except as written below)
Jack D. Furst, J. Michael Gearon, Jr.,
Randall T. Mays and Thomas H. Stoner.          [_]     [_]                  [_]



Withheld for the following (write the nominee's name(s) in the space below):

- ----------------------------------------------
- ----------------------------------------------
- ----------------------------------------------

2.  To approve an amendment to
the Company's 1997 Stock Option                   For      Against      Abstain
Plan to increase the number of shares
for which options may be granted from             [_]        [_]          [_]
15,000,000 to 24,000,000.

3.  To approve the adoption of the                For      Against      Abstain
ATC Teleports, Inc. 1999
Stock Option Plan.                                [_]        [_]          [_]


4.  To approve the adoption of the Kline          For      Against      Abstain
Iron & Steel Co., Inc. 2000 Option Plan.

                                                  [_]        [_]          [_]


5. To approve the adoption of the                 For      Against      Abstain
American Tower Corporation 2000
Employee Stock Purchase Plan.                     [_]        [_]          [_]

6. Ratification of Deloitte & Touche LLP as       For      Against      Abstain
independent auditors for 2000.
                                                  [_]        [_]          [_]





Dated:____________________, 2000            Signature(s)________________________

                                            NOTE: Please sign exactly as name
                                            appears hereon. Joint owners should
                                            each sign. When signing as attorney,
                                            executor, administrator, trustee or
                                            guardian, please give full title as
                                            such. If a corporation, please sign
                                            in full company name by an
                                            authorized officer or if a
                                            partnership please sign in
                                            partnership name by an authorized
                                            person.


                                      -2-