EXHIBIT 2.1
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                           THIRD AMENDED AND RESTATED
                          CERTIFICATE OF INCORPORATION
                                       of
                           SPECTRASITE HOLDINGS, INC.

         SpectraSite Holdings, Inc., a corporation organized and existing under
the laws of the State of Delaware (the "CORPORATION"), hereby certifies as
follows:

         FIRST: The name of the Corporation is SpectraSite Holdings, Inc. The
Corporation was originally incorporated under the name "Integrated Site
Development, Inc." and the original Certificate of Incorporation of the
Corporation was filed with the Secretary of State of Delaware on April 25, 1997.

         SECOND: A petition for relief under Chapter 11 of the Bankruptcy Code,
11 U.S.C. Sections 101 ET SEQ., having been filed on November 15, 2002 in the
United States Bankruptcy Court, Eastern District of North Carolina, Raleigh
Division, and under the Plan of Reorganization dated November 27, 2002, as the
same may be amended or modified, from time to time (the "PLAN OF
REORGANIZATION"), and inter ALIA, Sections 1123 and 1129 of the Bankruptcy Code,
11 U.S.C. Sections 1123 and 1129, in accordance with Section 303 of the General
Corporation Law of the State of Delaware (the "GENERAL CORPORATION LAW") and
pursuant to the order of said court dated January 28, 2003, this Third Amended
and Restated Certificate of Incorporation restates and further amends the
provisions of the Certificate of Incorporation of the Corporation.



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         THIRD: The text of the Second Amended and Restated Certificate of
Incorporation, is hereby amended and restated to read in its entirety as
follows:

         1.       NAME. The name of the corporation is "SpectraSite, Inc." (the
"CORPORATION").

         2.       ADDRESS; REGISTERED OFFICE AND AGENT. The address of the
Corporation's registered office is 1209 Orange Street, City of Wilmington,
County of New Castle, State of Delaware 19801; and the name of its registered
agent at such address is The Corporation Trust Company.

         3.       PURPOSES. The purpose of the Corporation is to engage in any
lawful act or activity for which corporations may be organized under the General
Corporation Law.

         4.       CAPITAL STOCK:

                  4.1      The total number of shares of all classes of stock
that the Corporation shall have authority to issue is: 290,000,000 shares,
divided into 250,000,000 shares of Common Stock, of the par value of $.01 each
(the "COMMON STOCK"), and 40,000,000 shares of Preferred Stock, of the par value
of $.01 per share (the "PREFERRED STOCK"). Each share of the Corporation's
common stock, $.001 par value, per share, issued and outstanding or held in
treasury immediately prior to the effectiveness of this Third Amended and
Restated Certificate of Incorporation is automatically and



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without any further action of the Corporation or the holders thereof cancelled
pursuant to the Plan of Reorganization.

                  4.2      The Board of Directors of the Corporation (the
"BOARD") is hereby expressly authorized, by resolution or resolutions thereof,
to provide, out of the unissued shares of Preferred Stock, for series of
Preferred Stock and, with respect to each such series, to fix the number of
shares constituting such series and the designation of such series, the voting
powers (if any) of the shares of such series, and the preferences and relative,
participating, optional or other special rights, if any, and any qualifications,
limitations or restrictions thereof, of the shares of such series. The powers,
preferences and relative, participating, optional and other special rights of
each series of Preferred Stock, and the qualifications, limitations or
restrictions thereof, if any, may differ from those of any and all other series
at any time outstanding. Notwithstanding the foregoing, the Board shall not have
the authority to issue any series of Preferred Stock pursuant to this Section
4.2 if the purpose of such issuance is to implement, or to facilitate the
implementation of, a "poison pill" or other similar shareholder rights plan or
other plan whose primary intent is to impede an acquisition of the Corporation
or an acquisition of substantially all of the Corporation's subsidiaries or
assets, unless any such issuance is approved by the affirmative vote of the
holders of at least a majority of the voting power of the shares of the then
outstanding voting stock of the Corporation, voting together as a single class.



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                  4.3      Subject to applicable law, each holder of Common
Stock, as such, shall be entitled to one vote for each share of Common Stock
held of record by such holder on all matters on which stockholders generally are
entitled to vote.

                  4.4      Subject to applicable law and the rights, if any, of
the holders of any outstanding series of Preferred Stock, dividends may be
declared and paid on the Common Stock at such times and in such amounts as the
Board in its discretion shall determine.

                  4.5      Upon the dissolution, liquidation or winding up of
the Corporation, subject to the rights, if any, of the holders of any
outstanding series of Preferred Stock, the holders of the Common Stock shall be
entitled to receive the assets of the Corporation available for distribution to
its stockholders ratably in proportion to the number of shares held by them.

                  4.6      To the extent required by Section 1123(a)(6) of the
U.S. Bankruptcy Code (11 U.S.C. ss. 1123(a)(6)), no nonvoting equity securities
of the Corporation shall be issued. This provision shall have no further force
and effect beyond that required by Section 1123(a)(6) and is applicable only for
so long as such section is in effect and applicable to the Corporation.

         5.       BOARD OF DIRECTORS.

                  5.1      NUMBER OF DIRECTORS. The business and affairs of the
Corporation shall be managed by, or under the direction of, the Board. Except as



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otherwise provided for or fixed pursuant to the provisions of Article 4 of this
Third Amended and Restated Certificate of Incorporation relating to the rights
of the holders of any series of Preferred Stock to elect additional directors,
the total number of directors constituting the entire Board shall be not less
than 3 nor more than 12, with the then-authorized number of directors being
fixed from time to time by the Board.

                  During any period when the holders of any series of Preferred
Stock have the right to elect additional directors as provided for or fixed
pursuant to the provisions of Article 4 hereof, then upon commencement and for
the duration of the period during which such right continues: (i) the then
otherwise total authorized number of directors of the Corporation shall
automatically be increased by such specified number of directors, and the
holders of such Preferred Stock shall be entitled to elect the additional
directors so provided for or fixed pursuant to said provisions, and (ii) each
such additional director shall serve until such director's successor shall have
been duly elected and qualified, or until such director's right to hold such
office terminates pursuant to said provisions, whichever occurs earlier, subject
to his or her earlier death, disqualification, resignation or removal. Except as
otherwise provided by the Board in the resolution or resolutions establishing
such series, whenever the holders of any series of Preferred Stock having such
right to elect additional directors are divested of such right pursuant to the
provisions of such stock, the terms of office of all such additional directors
elected by the holders of such stock, or elected to fill any vacancies resulting
from the death, resignation, disqualification or removal of such additional
directors, shall



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forthwith terminate and the total and authorized number of directors of the
Corporation shall be reduced accordingly.

                  5.2      VACANCIES AND NEWLY CREATED DIRECTORSHIPS. Subject to
the rights of the holders of any one or more series of Preferred Stock then
outstanding, newly created directorships resulting from any increase in the
authorized number of directors or any vacancies in the Board resulting from
death, resignation, retirement, disqualification, removal from office or other
cause may be filled by a majority of the remaining directors then in office,
although less than a quorum of the Board, or by a sole remaining director.

                  5.3      REMOVAL OF DIRECTORS. Except for such additional
directors, if any, as are elected by the holders of any series of Preferred
Stock as provided for or fixed pursuant to the provisions of Article 4 hereof ,
any director, or the entire Board, may be removed from office at any time, with
or without cause, by the holders of a majority of the shares of the Corporation
then entitled to vote generally in the election of directors.

                  5.4      ELECTION OF DIRECTORS. Unless and except to the
extent that the By-laws of the Corporation (the "BY-LAWS") shall so require, the
election of directors of the Corporation need not be by written ballot.

         6.       LIMITATION OF LIABILITY. To the fullest extent permitted under
the General Corporation Law, as amended from time to time, no director of the
Corporation shall be personally liable to the Corporation or its stockholders
for monetary damages for



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breach of fiduciary duty as a director.

         Any amendment, repeal or modification of the foregoing provision shall
not adversely affect any right or protection of a director of the Corporation
hereunder in respect of any act or omission occurring prior to the time of such
amendment, repeal or modification.

         7.       INDEMNIFICATION.

                  7.1      RIGHT TO INDEMNIFICATION. The Corporation shall
indemnify and hold harmless, to the fullest extent permitted by applicable law
as it presently exists or may hereafter be amended, any person (a "COVERED
PERSON") who was or is made or is threatened to be made a party or is otherwise
involved in any action, suit or proceeding, whether civil, criminal,
administrative or investigative (a "PROCEEDING"), by reason of the fact that he
or she, or a person for whom he or she is the legal representative, is or was at
any time from and after the effective date of the Plan of Reorganization, a
director or officer of the Corporation or, while a director or officer of the
Corporation, is or was at any time from and after the effective date of the Plan
of Reorganization, serving at the request of the Corporation as a director,
officer, employee or agent of another corporation or of a partnership, joint
venture, trust, enterprise or nonprofit entity (an "OTHER ENTITY"), including
service with respect to employee benefit plans, against all liability and loss
suffered and expenses (including attorneys' fees) reasonably incurred by such
Covered Person. Notwithstanding the preceding sentence, except as otherwise
provided in Section 7.3, the Corporation shall be required to indemnify a
Covered Person in connection with



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a Proceeding (or part thereof) commenced by such Covered Person only if the
commencement of such Proceeding (or part thereof) by the Covered Person was
authorized by the Board.

                  7.2      PREPAYMENT OF EXPENSES. The Corporation shall pay the
expenses (including attorneys' fees) incurred by a Covered Person in defending
any Proceeding in advance of its final disposition; PROVIDED, HOWEVER, that, to
the extent required by applicable law, such payment of expenses in advance of
the final disposition of the Proceeding shall be made only upon receipt of an
undertaking by the Covered Person to repay all amounts advanced if it should be
ultimately determined that the Covered Person is not entitled to be indemnified
under this Article 7 or otherwise.

                  7.3      CLAIMS. If a claim for indemnification or advancement
of expenses under this Article 7 is not paid in full within 30 days after a
written claim therefor by the Covered Person has been received by the
Corporation, the Covered Person may file suit to recover the unpaid amount of
such claim and, if successful in whole or in part, shall be entitled to be paid
the expense of prosecuting such claim. In any such action the Corporation shall
have the burden of proving that the Covered Person is not entitled to the
requested indemnification or advancement of expenses under applicable law.

                  7.4      NONEXCLUSIVITY OF RIGHTS. The rights conferred on any
Covered Person by this Article 7 shall not be exclusive of any other rights that
such Covered Person may have or hereafter acquire under any statute, provision
of this Third



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Amended and Restated Certificate of Incorporation, the By-laws, agreement, vote
of stockholders or disinterested directors or otherwise.

                  7.5      OTHER SOURCES. The Corporation's obligation, if any,
to indemnify or to advance expenses to any Covered Person who was or is serving
at its request as a director, officer, employee or agent of an Other Entity
shall be reduced by any amount such Covered Person may collect as
indemnification or advancement of expenses from such Other Entity.

                  7.6      AMENDMENT OR REPEAL. Any repeal or modification of
the foregoing provisions of this Article 7 shall not adversely affect any right
or protection hereunder of any Covered Person in respect of any act or omission
occurring prior to the time of such repeal or modification.

                  7.7      OTHER INDEMNIFICATION AND PREPAYMENT OF EXPENSES;
INSURANCE. This Article 7 shall not limit the right of the Corporation, to the
extent and in the manner permitted by applicable law, to indemnify and to
advance expenses to persons other than Covered Persons when and as authorized by
appropriate corporate action. The Corporation may purchase and maintain
insurance on its own behalf and on behalf of any Covered Person, whether or not
the Corporation would have the power to indemnify such person against such
liability under the General Corporation Law or otherwise.

         8.       ADOPTION, AMENDMENT AND/OR REPEAL OF BY-LAWS. In furtherance
and not in limitation of the powers conferred by the laws of the State of
Delaware, the



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Board is expressly authorized to make, alter and repeal the By-laws, subject to
the power of the stockholders of the Corporation to alter or repeal any By-law
whether adopted by them or otherwise.

         9.       CERTIFICATE AMENDMENTS - RIGHT TO AMEND. The Corporation
reserves the right at any time, and from time to time, to amend, alter, change
or repeal any provision contained in this Third Amended and Restated Certificate
of Incorporation, and other provisions authorized by the laws of the State of
Delaware at the time in force may be added or inserted, in the manner now or
hereafter prescribed by applicable law; and all rights, preferences and
privileges of whatsoever nature conferred upon stockholders, directors or any
other persons whomsoever by and pursuant to this Third Amended and Restated
Certificate of Incorporation in its present form or as hereafter amended are
granted subject to the rights reserved in this Article 9.

         FOURTH: The amendments and restatement effected herein were
authorized pursuant to Sections 242, 245 and 303 of the General Corporation Law.




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         IN WITNESS WHEREOF, the Corporation has caused this Third Amended and
Restated Certificate of Incorporation to be executed by Stephen H. Clark, its
President and Chief Executive Officer, who hereby acknowledges under penalties
of perjury that the facts herein stated are true and that this certificate is
his act and deed, this 10th day of February, 2003.


                                     SPECTRASITE HOLDINGS, INC.


                                     By: /s/ Stephen H. Clark
                                         ---------------------------------------
                                         Stephen H. Clark
                                         President and Chief Executive Officer