EXHIBIT 10.6
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THESE SECURITIES HAVE BEEN ISSUED PURSUANT TO EXEMPTIONS FOR NONPUBLIC OFFERINGS
FROM THE  REGISTRATION  REQUIREMENTS  OF THE SECURITIES ACT OF 1933, AS AMENDED,
AND APPLICABLE STATE SECURITIES LAWS, AND, ACCORDINGLY, THESE SECURITIES MAY NOT
BE RESOLD OR  OTHERWISE  DISPOSED  OF UNLESS,  IN THE  OPINION OF COUNSEL FOR OR
SATISFACTORY TO THE ISSUER,  REGISTRATION  UNDER THE APPLICABLE FEDERAL OR STATE
SECURITIES  LAWS IS NOT REQUIRED OR  COMPLIANCE  IS MADE WITH SUCH  REGISTRATION
REQUIREMENTS.

         VOID AFTER 5:00 P.M. NEW YORK TIME, ON MARCH 6, 2002



         WARRANT TO PURCHASE 402,500 SHARES OF CLASS A COMMON STOCK

                                       OF

                        SBA COMMUNICATIONS CORPORATION

         This is to certify that, FOR VALUE RECEIVED, ALEX. BROWN & SONS
INCORPORATED  or  its  registered   assigns   pursuant  to  Section  (d)  hereof
("Holder"), is entitled to purchase,  subject to the provisions of this Warrant,
from SBA  Communications  Corporation,  a Florida  corporation  (the "Company"),
402,500 fully paid,  validly issued and  nonassessable  shares of Class A Common
Stock, par value $.01 per share, of the Company ("Class A Common Stock"), at the
exercise price of $3.726708075 per share, subject to adjustment,  until March 6,
2002.  The  number  of shares of Class A Common  Stock to be  received  upon the
exercise  of this  Warrant  and the  price to be paid for each  share of Class A
Common  Stock may be  adjusted  from time to time as  contained  in Section  (h)
hereof.  The shares of Class A Common Stock deliverable upon such exercise,  and
as adjusted from time to time, are hereinafter sometimes referred to as "Warrant
Shares," and the exercise price of a share of Class A Common Stock,  as adjusted
from time to time, is hereinafter sometimes referred to as the "Exercise Price."

         (a) EXERCISE OF WARRANT;  NOTIFICATION  OF EXPIRATION  DATE OF WARRANT.
The Warrant may be exercised  as to a minimum of 100 Warrant  Shares at any time
or from  time to time,  until  5:00  P.M.  New York  time on March 6,  2002 (the
"Expiration  Date"),  provided,  however,  that  if such  day is a day on  which
banking  institutions  in the State of New York are  authorized by law to close,
then on the next  succeeding  day which shall not be such a day. The Warrant may
be  exercised  by  presentation  and  surrender  hereof  to the  Company  at its
principal office, or at the office of its stock transfer agent, if any, with the
Purchase  Form  annexed  hereto duly  executed  (with  signature  guaranteed  if
required by the Company or its stock transfer  agent) and accompanied by payment
of the Exercise  Price for the number of Warrant  Shares  specified in such form
and any applicable  taxes.  The purchase price for any Warrant Shares  purchased
pursuant  to the  exercise  of this  Warrant  shall  be paid in full  upon  such
exercise  in cash or by  certified  or bank  check  or  pursuant  to a  cashless
exercise  procedure  whereby the  Warrant  Shares  issued upon  exercise of this
Warrant will be sold with Holder  receiving the difference  between the Exercise
Price and the sale price, in cash, and the Company  receiving the Exercise Price
for the Warrant Shares, in cash, or any

                                                       

 
combination of the foregoing  methods of paying the Exercise  Price.  As soon as
practicable  after each such exercise of the Warrants,  but not later than seven
(7) business  days from the date of such  exercise,  the Company shall issue and
deliver to the Holder a  certificate  or  certificates  for the  Warrant  Shares
issuable  upon  such  exercise,  registered  in the  name of the  Holder  or the
Holder's  designee,  except in the case of a cashless  exercise.  If the Warrant
should be  exercised  in part only,  the Company  shall,  upon  surrender of the
Warrant for  cancellation,  execute and  deliver a new  Warrant  evidencing  the
rights of the Holder  thereof to  purchase  the  balance of the  Warrant  Shares
purchasable  thereunder.  In the event of a cash  exercise,  upon receipt by the
Company of the  Warrant at its  office,  or by the stock  transfer  agent of the
Company at its office,  in proper form for exercise,  together with the exercise
price  thereof and taxes as aforesaid in cash or certified or bank check and the
investment  letter  described below, the Holder shall be deemed to be the holder
of record of the shares of Class A Common  Stock  issuable  upon such  exercise,
notwithstanding  that the stock  transfer  books of the  Company  shall  then be
closed or that  certificates  representing  such shares of Class A Common  Stock
shall not then be  physically  delivered  to the Holder.  In order to assure the
availability of an exemption from  registration  under the federal or applicable
state  securities  laws,  the Company may  condition the exercise of the Warrant
upon the Holder  delivering to the Company an  investment  letter in the form as
customarily  used by the  Company  from  time to time  in  connection  with  the
exercise of non-registered options and warrants which are issued by the Company.
It is further understood that certificates for the Warrant Shares, if any, to be
issued  upon  exercise  of the  Warrant  may  contain  a  restrictive  legend in
accordance with Section (g) hereof.

         Notwithstanding anything herein to the contrary, the Company shall mail
to the Holder,  by  certified  mail,  return  receipt  requested,  notice of the
Expiration  Date of the Warrants,  no later than 60 days prior to the Expiration
Date.  To the extent the Company  shall fail to send the required  notice at the
time and in the manner set forth in the preceding sentence,  the Expiration Date
of the Warrants  shall be extended to a date 60 days  following  the date that a
written  notice of the  Expiration  Date of the  Warrants  from the  Company  is
received by the Holder.

         (b)  RESERVATION OF SHARES.  The Company shall at all times reserve for
issuance  and/or delivery upon exercise of this Warrant such number of shares of
its Class A Common Stock as shall be required  for  issuance  and delivery  upon
exercise of the  Warrants.  If the Class A Common Stock is or becomes  listed on
any national  securities  exchange or the Nasdaq  National  Market,  the Company
shall also list such  shares on such  exchange  subject to notice of issuance or
maintain  the listing of its Class A Common Stock on the Nasdaq  system,  as the
case may be.

         (c)  FRACTIONAL  SHARES.  No  fractional  shares or scrip  representing
fractional shares shall be issued upon the exercise of the Warrant. With respect
to any  fraction of a share  called for upon any  exercise  hereof,  the Company
shall pay to the Holder an amount in cash equal to such  fraction  multiplied by
the current market value of a share, determined as follows:

                  (1) If the  Class A  Common  Stock  is  listed  on a  national
         securities  exchange or admitted to unlisted trading privileges on such
         exchange  or listed  for  trading on the Nasdaq  National  Market,  the
         current market value shall be the last reported sale price of the Class
         A Common  Stock on such  exchange  or system on the last  business  day
         prior to the date of

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         exercise  of this  Warrant or if no such sale is made on such day,  the
         average  closing bid and asked prices for such day on such  exchange or
         system;

                  (2) If the Class A Common  Stock is not so listed or  admitted
         to unlisted trading  privileges,  the current market value shall be the
         mean of the last reported bid and asked prices reported by the National
         Quotation  Bureau,  Inc., on the last business day prior to the date of
         the exercise of this Warrant; or

                  (3) If the Class A Common  Stock is not so listed or  admitted
         to  unlisted  trading  privileges  and bid and asked  prices are not so
         reported,  the current  market value shall be an amount,  not less than
         the book value  thereof as at the end of the most recent fiscal year of
         the Company  ending  prior to the date of the  exercise of the Warrant,
         determined in such reasonable  manner as may be prescribed by the Board
         of Directors of the Company.

         (d) EXCHANGE,  TRANSFER,  ASSIGNMENT OR LOSS OF WARRANT. The Warrant is
exchangeable,  without expense,  at the option of the Holder,  upon presentation
and  surrender  hereof to the  Company  or at the  office of its stock  transfer
agent,  if any, for other  Warrants of  different  denominations  entitling  the
Holder thereof to purchase in the aggregate the same number of shares of Class A
Common Stock purchasable  hereunder.  Subject to Section (g) hereof,  the Holder
may transfer or assign the  Warrant,  in whole or in part and from time to time.
Upon surrender of this Warrant to the Company at its principal  office or at the
office of its stock transfer  agent,  if any, with the  Assignment  Form annexed
hereto duly executed (with signature  guaranteed,  if required by the Company or
its stock  transfer  agent) and funds  sufficient  to pay any transfer  tax, the
Company shall, without charge,  execute and deliver a new Warrant in the name of
the  assignee or  assignees  named in such  instrument  of  assignment  and this
Warrant shall  promptly be canceled.  This Warrant may be divided by or combined
with other Warrants which carry the same rights upon presentation  hereof at the
principal office of the Company or at the office of its stock transfer agent, if
any,  together with a written notice  specifying the names and  denominations in
which new  Warrants are to be issued and signed by the Holder  hereof.  The term
"Warrant" as used herein  includes  any Warrants  into which this Warrant may be
divided or exchanged. Upon receipt by the Company of evidence satisfactory to it
of the loss, theft,  destruction or mutilation of this Warrant,  and in the case
of loss, theft or destruction, of reasonable satisfactory  indemnification,  and
upon surrender and cancellation of this Warrant, if mutilated,  the Company will
execute and deliver a new Warrant of like tenor, date and amount.

         (e) RIGHTS OF THE HOLDER.  The Holder shall not, by virtue  hereof,  be
entitled to any rights of a shareholder in the Company, either at law or equity,
and the rights of the Holder are limited to those  expressed  in the Warrant and
are not enforceable against the Company except to the extent set forth herein.

         (f)  NOTICES  TO  WARRANT  HOLDERS.  So long as this  Warrant  shall be
outstanding,  (i) if the Company shall pay any dividend or make any distribution
upon the common stock of the Company,  or (ii) if the Company shall offer to the
holders of common stock for  subscription  or purchase by them any shares of any
class or any other rights, or (iii) if any capital

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reorganization  of the  Company,  reclassification  of the capital  stock of the
Company,   consolidation   or  merger  of  the  Company  with  or  into  another
corporation, sale, lease or transfer of all or substantially all of the property
and assets of the Company to another  corporation,  or voluntary or  involuntary
dissolution, liquidation or winding up of the Company shall be effected, then in
any such case,  the Company  shall cause to be mailed by  certified  mail to the
Holder or any holder of a Warrant executed and/or delivered  pursuant to Section
(a) or Section  (d), at least 15 days prior to the date  specified in (x) or (y)
below,  as the  case  may be, a notice  containing  a brief  description  of the
proposed  action and  stating  the date on which (x) a record is to be taken for
the   purpose  of  such   dividend,   distribution   or  rights,   or  (y)  such
reclassification,  reorganization,  consolidation,  merger,  conveyance,  lease,
dissolution,  liquidation or winding up is to take place and the date, if any is
to be fixed, as of which the holders of common stock or other  securities  shall
receive  cash  or  other  property   deliverable  upon  such   reclassification,
reorganization,  consolidation,  merger, conveyance, dissolution, liquidation or
winding up.

         (g)       SECURITIES LAW COMPLIANCE.

                  (1)  The  Holder  of  the  Warrant,   by  acceptance   hereof,
         acknowledges that the Warrant and the shares of Class A Common Stock to
         be issued upon exercise hereof or conversion thereof are being acquired
         solely for the  Holder's own account and not as a nominee for any other
         party,  and for investment,  and that the Holder will not offer,  sell,
         transfer,  assign or otherwise dispose of this Warrant or any shares of
         Class A Common Stock to be issued upon  exercise  hereof or  conversion
         thereof except under  circumstances that will not result in a violation
         of the Act or any state  securities laws. Upon exercise of the Warrant,
         the Holder shall, if requested by the Company, confirm in writing, in a
         form  satisfactory  to the  Company,  that the shares of Class A Common
         Stock so  purchased  are being  acquired  solely for the  Holder's  own
         account and not as a nominee for any other party,  for investment,  and
         not with a view toward distribution or resale.

                  (2) If  appropriate,  the Warrant and any Warrants issued upon
         exercise or  substitution  or upon  assignment or transfer  pursuant to
         Section (a) or Section (d), as the case may be, and all shares of Class
         A Common Stock issued upon exercise hereof or conversion  thereof shall
         be stamped or imprinted with legends setting forth the  restrictions on
         transfer arising under applicable federal and state securities laws.

         (h)      ADJUSTMENTS TO EXERCISE PRICE.

                  (i) Subdivision, Combination or Reclassification of Class A
                      -------------------------------------------------------
                      Common Stock.
                      ------------

                     (A) If the Company shall effect a subdivision of its shares
                         of Common Stock into a greater number of such shares
                         or a combination of such shares into a lesser number
                         of shares, whether by forward or reverse stock split,
                         stock dividend (payable in shares of Common Stock) or
                         otherwise, the Exercise Price shall be proportionally
                         increased or

                                        4

 
               reduced,  as the case may be, to reflect the effectuation of such
               subdivision or combination.

          (B)  If  the  Company  shall  effect  a  capital   reorganization   or
               reclassification  of the Common Stock or any  distribution by the
               Company to holders of Class A Common  Stock,  whether in the form
               of stock,  debt  securities,  or other  assets or property of the
               Company,  (each, an "Adjustment Event"),  then, as a condition of
               such  Adjustment  Event,  lawful and adequate  provision shall be
               made whereby the holders of the Warrant shall thereafter have the
               right to acquire  and receive  such shares of stock,  securities,
               assets or  property  as would have been  issuable or payable as a
               result of such  Adjustment  Event with  respect to or in exchange
               for such number of outstanding shares of the Class A Common Stock
               as would have been  received as if such  Warrant  were  exercised
               immediately prior to the consummation of such Adjustment Event.

          (C)  In the event that an  Adjustment  Event shall occur by means of a
               merger,  consolidation,  combination,  share exchange, or sale or
               lease of all or substantially all the assets of the Company, then
               as a condition  of such  Adjustment  Event,  lawful and  adequate
               provision  shall be made whereby the holders of the Warrant shall
               thereafter  have the rights to acquire and receive upon  exercise
               of their Warrant,  such shares of stock,  securities or assets as
               would have been  issuable  or payable as part of such  Adjustment
               Event  with  respect  to  or  in  exchange  for  such  number  of
               outstanding shares of the Class A Common Stock as would have been
               received  upon  exercise  of  the  Warrant  (in  all   instances)
               immediately  before such Adjustment  Event,  and in any such case
               appropriate  provisions  shall be made with respect to the rights
               and  interests  of the  holders  of the  Warrant  such  that  the
               provisions hereof (including  without  limitation  provisions for
               adjustments  of the Exercise Price and of the number of shares of
               Class A Common Stock  acquirable and receivable upon the exercise
               of the Warrant) shall  thereafter be  applicable,  in relation to
               any shares of stock,  securities or assets thereafter deliverable
               upon  the  conversion  of the  Warrant  (including  an  immediate
               adjustment,  by reason of such Adjustment Event of the Warrant to
               the value for the Class A Common Stock  reflected by the terms of
               such Adjustment  Event if the value so reflected is less than the
               Exercise  Price in effect  immediately  prior to such  Adjustment
               Event).  In the event of an Adjustment Event as a result of which
               a number of shares of Common Stock of the surviving or purchasing
               Company is greater or lesser  than the number of shares of Common
               Stock  of the  Company  outstanding  immediately  prior  to  such
               Adjustment Event, then the

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               Exercise  Price in effect  immediately  prior to such  Adjustment
               Event shall be adjusted in the same manner as though there were a
               subdivision or combination of the  outstanding  shares of Class A
               Common Stock of the Company. The Company will not effect any such
               Adjustment  Event  unless prior to the  consummation  thereof the
               successor  corporation (if other than the Company) resulting from
               such  consolidation  or merger or the  purchase  or lease of such
               assets shall assume by written  instrument mailed or delivered to
               the  holders  of the  Warrant  at the last  address  of each such
               holder  appearing on the books of the Company,  the obligation to
               deliver to each such holder such shares of stock,  securities  or
               assets as, in  accordance  with the  foregoing  provisions,  such
               holder may be entitled.

 (ii)  Issuance of Common Stock. Except as provided herein, if and whenever the
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       Company shall issue or sell, or shall be deemed to have issued or sold,
       any shares of its Class A Common Stock, or options, warrants or other
       rights to purchase Class A Common Stock or securities convertible into
       Class A Common Stock, for a consideration per share less than the
       Exercise Price in effect immediately prior to the time of such issuance
       or sale, then forthwith upon such issuance or sale, the Exercise Price
       shall, subject to subparagraphs (A) to (F) of Paragraph (h)(iii), be
       reduced to:

       (A)  For  issuances  or sales on or before 18 months after the date of
            the issuance of this Warrant, the Exercise Price shall equal such
            issuance or sale price.

       (B)  For issuances or sales after 18 months from the date of the issuance
            of this Warrant, the Exercise Price shall be determined by
            multiplying the Exercise Price in effect immediately prior to such
            issuance or sale by a fraction; the numerator of which shall be (1)
            the number of shares of Class A Common Stock outstanding immediately
            prior to the issuance of such additional shares of Class A Common
            Stock, plus (2) the number of shares of Class A Common Stock which
            the net aggregate consideration, if any, received by the Company for
            the total number of such additional shares of Class A Common Stock
            so issued would purchase at the Exercise Price in effect immediately
            prior to such issuance, and; the denominator of which shall be (1)
            the number of shares of Class A Common Stock outstanding immediately
            prior to the issuance of such additional shares of Class A Common
            Stock plus (2) the number of such additional shares of Class A
            Common Stock so issued.

                                       6

 
(iii)  For purposes of determining the adjusted Exercise Price under Paragraph
       (h)(ii)(A) and (B), the following subsections (A) to (F), inclusive,
       shall be applicable:

          (A)  Issuance  of Rights or  Options.  Except  as  provided  Paragraph
               -------------------------------
               (h)(iv),  in case at any time  the  Company  shall in any  manner
               grant  (whether   directly  or  by  assumption  in  a  merger  or
               otherwise)  any rights to subscribe  for or to  purchase,  or any
               options for the purchase of, Class A Common Stock or any stock or
               other  securities  convertible  into or exchangeable  for Class A
               Common  Stock  (such  rights  or  options   being  herein  called
               "Options"  and  such   convertible  or   exchangeable   stock  or
               securities being herein called "Convertible  Securities") whether
               or not such  Options or the right to convert or exchange any such
               Convertible Securities are immediately exercisable, and the price
               per share for which such Class A Common  Stock is  issuable  upon
               the  exercise of such Options or upon  conversion  or exchange of
               such Convertible Securities (determined by dividing (x) the total
               amount,  if  any,  received  or  receivable  by  the  Company  as
               consideration for the granting of such Options,  plus the minimum
               aggregate  amount  of  additional  consideration  payable  to the
               Company upon the exercise of all such Options,  plus, in the case
               of such  Options  which  relate to  Convertible  Securities,  the
               minimum  aggregate  amount of additional  consideration,  if any,
               payable upon the issue or sale of such Convertible Securities and
               upon the conversion or exchange thereof, by (y) the total maximum
               number  of  shares  of Class A  Common  Stock  issuable  upon the
               exercise of such Options)  shall be less than the Exercise  Price
               in effect  immediately  prior to the time of the granting of such
               Option, then the total maximum number of shares of Class A Common
               Stock  issuable  upon  the  exercise  of  such  Options  or  upon
               conversion  or  exchange  of the  total  maximum  amount  of such
               Convertible Securities issuable upon the exercise of such Options
               shall (as of the date of granting  of such  Options) be deemed to
               be  outstanding  and to have been  issued by the Company for such
               price per share.  No  adjustment  of the Exercise  Price shall be
               made upon the  actual  issuance  of such  Convertible  Securities
               except as otherwise provided in subsection (C) below.

          (B)  Issuance of Convertible Securities.  In case the Company shall in
               ----------------------------------
               any manner issue  (whether  directly or by assumption in a merger
               or otherwise) or sell any Convertible Securities,  whether or not
               the rights to  exchange  or convert  thereunder  are  immediately
               exercisable,  and the price per  share  for  which  such  Class A
               Common  Stock  is  issuable  upon  such  conversion  or  exchange
               (determined  by  dividing  (x)  the  total  amount   received  or
               receivable by the Company as

                                                         7

 
               consideration  for the  issuance  or  sale  of  such  Convertible
               Securities,  plus the  minimum  aggregate  amount  of  additional
               consideration, if any, payable to the Company upon the conversion
               or exchange thereof, by (y) the total maximum number of shares of
               Class A Common Stock  issuable upon the conversion or exchange of
               all such Convertible  Securities) shall be less than the Exercise
               Price in effect immediately prior to the time of such issuance or
               sale,  then the  total  maximum  number  of all such  Convertible
               Securities  shall  (as of the  date of the  issue or sale of such
               Convertible  Securities) be deemed to be outstanding  and to have
               been  issued  and sold by the  Company  for such price per share,
               provided  that,  except as otherwise  specified in subsection (C)
               below, no adjustment of the Exercise Price shall be made upon the
               actual  issue of such Class A Common  Stock upon  exercise of any
               Options for which  adjustments of the Exercise Price have been or
               are to be made pursuant to other provisions of this Paragraph (h)
               and no further  adjustment of the Exercise Price shall be made by
               reason of such issuance or sale.

          (C)  Change in Option Price or Conversion Rate. If the purchase price
               -----------------------------------------
               provided for in any Option referred to in  subparagraph  (A), the
               additional consideration,  if any, payable upon the conversion or
               exchange   of  any   Convertible   Securities   referred   to  in
               subparagraphs  (A) or (B),  or the rate at which any  Convertible
               Securities   referred  to  in   subparagraphs   (A)  or  (B)  are
               convertible into or exchangeable for Class A Common Stock,  shall
               change at any time (other  than under or by reason of  provisions
               designed  to protect  against  dilution  of the type set forth in
               paragraph  (h), the Exercise  Price in effect at the time of such
               change shall  forthwith be readjusted to the Exercise Price which
               would  have  been in  effect  at such  time had such  Options  or
               Convertible   Securities  still  outstanding  provided  for  such
               changed purchase price, additional  consideration,  or conversion
               rate, as the case may be, at the time initially  granted,  issued
               or  sold.  If the  purchase  price  provided  for  in any  Option
               referred  to  in  subsection  (A),  or  the  rate  at  which  any
               Convertible  Securities  referred to in subparagraphs  (A) or (B)
               are convertible  into or  exchangeable  for Class A Common Stock,
               shall be  reduced  at any time  under or by reason or  provisions
               with respect thereto designed to protect against  dilution,  then
               in case of the delivery of Class A Common Stock upon the exercise
               of any such  Option or upon  conversion  or  exchange of any such
               Convertible Security, the Exercise Price then in effect hereunder
               shall  forthwith be adjusted to such  respective  amount as would
               have been obtained had such Option or Convertible  Security never
               been issued as to such Class A Common  Stock and had  adjustments
               been made upon the issuance of the shares of Class A

                                        8

 
               Common Stock  delivered as aforesaid,  but only if as a result of
               such  adjustment the Exercise  Price then in effect  hereunder is
               hereby reduced.

          (D)  Treatment of Expired Options and Unexercised Convertible
               --------------------------------------------------------
               Securities. On the expiration of any Option or the termination of
               ----------
               any right to convert or exchange any Convertible Securities, the
               Exercise Price then in effect hereunder shall forthwith be
               increased to the Exercise Price which would have been in effect
               at the time of such expiration or termination had such Option or
               Convertible Securities, to the extent outstanding immediately
               prior to such expiration or termination, never been issued.

          (E)  Adjustment  of Number of  Shares.  Upon  each  adjustment  in the
               --------------------------------
               Exercise  Price,  the  number of  shares of Class A Common  Stock
               purchasable  hereunder  shall be adjusted,  to the nearest  whole
               share,  to the  product  obtained  by  multiplying  the number of
               shares  purchasable  immediately  prior to such adjustment in the
               Exercise Price by a fraction, the numerator of which shall be the
               Exercise  Price  immediately  prior  to such  adjustment  and the
               denominator  of which  shall be the  Exercise  Price  immediately
               thereafter.

          (F)  Integral  Transaction.  In case any  Options  shall be  issued in
               ---------------------
               connection  with the  issue or sale of  other  securities  of the
               Company, together comprising one integral transaction in which no
               specific  consideration  is  allocated  to  such  Options  by the
               parties thereto, such Options shall be deemed to have been issued
               without consideration.

          (G)  Consideration  for  Stock.  In case any  shares of Class A Common
               -------------------------
               Stock, Options or Convertible  Securities shall be issued or sold
               or deemed to have been issued or sold for cash, the consideration
               received  therefor  shall be deemed to be the amount  received by
               the Company therefor. In case any shares of Class A Common Stock,
               Options, or Convertible  Securities shall be issued or sold for a
               consideration  other than cash,  the amount of the  consideration
               other than cash  received by the Company  shall be the fair value
               of such  consideration.  In case  any  shares  of  Class A Common
               Stock,  Options,  or  Convertible  Securities  shall be issued in
               connection  with any merger in which the Company is the surviving
               corporation, the amount of consideration therefor shall be deemed
               to be the  fair  value  of such  portion  of the net  assets  and
               business   of  the   non-surviving   corporation   as   shall  be
               attributable   to  such  Class  A  Common  Stock,   Options,   or
               Convertible  Securities,  as the case may be. In the event of any
               consolidation or merger of the Company in which the

                                       9

 
               Company is not the surviving corporation, or, in the event of any
               sale of all or substantially all of the assets of the Company for
               stock or other  securities of any  corporation,  this  subsection
               shall be applied in the same  manner as if the  Company  had been
               the surviving corporation in such consolidation or merger, or the
               purchasing  corporation in such sale of assets;  and for purposes
               of this sentence the Company shall be deemed:

               (1)  to have  issued  and sold a number  of shares of its Class A
                    Common Stock,  Options,  or Convertible  Securities equal to
                    the sum of (x) the number of shares of the Company's Class A
                    Common Stock actually outstanding,  (y) the number of shares
                    of the Company's  Class A Common Stock  acquirable  upon the
                    exercise of all outstanding  Options,  and (z) the number of
                    shares of the Company's Class A Common Stock acquirable upon
                    conversion of all outstanding Convertible Securities,  which
                    those  persons who were  security  holders of the  surviving
                    corporation  immediately  before  the  consummation  of  the
                    transaction  would have  received in exchange for the common
                    stock, options, and convertible  securities of the surviving
                    corporation held by them immediately  after  consummation of
                    the  transaction,  based on the exchange  ratio on which the
                    transaction was consummated  (i.e., the inverse of the ratio
                    pursuant to which the  Company's  Class A Common  Stock were
                    exchangeable  into the surviving  corporation's  securities)
                    and   assuming   that   Company   had  been  the   surviving
                    corporation; and

               (2)  to have received in exchange therefor a consideration  equal
                    to  the  fair   market   value   (immediately   before   the
                    consummation  of such  transaction)  of the assets (less the
                    liabilities)  of  the  surviving  corporation;  and  if  the
                    application  of this  sentence  results in adjustment of the
                    Exercise Price, then the determination of the Exercise Price
                    immediately  prior to such  merger,  consolidation,  or sale
                    shall be made  after  giving  effect to the  adjustment  set
                    forth  herein.  If the stock of the  surviving or purchasing
                    corporation  in such a transaction is publicly  traded,  the
                    market  value  of  such   corporation's   outstanding  stock
                    immediately  before  consummation  of the exchange  shall be
                    presumptive  evidence of the fair market value of its assets
                    (less liabilities).

     (iv) Notwithstanding   anything  in  Paragraph  (h)  to  the  contrary,  no
          adjustment shall be made to the Exercise Price upon (w) the issuance

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              of any shares of Class A Common Stock, options or Convertible
              Securities in connection with an acquisition by the Company or a
              merger in which the Company is the surviving corporation,
              calculated on a fully diluted basis and further provided such
              issuance is to the sellers of the acquired entity or assets or
              security of the merged entity and is made for fair value and the
              Board of Directors of the Company determines that the acquisition
              or merger is in the best interests of the Company and its
              stockholders; (x) the issuance of any shares of Class A Common
              Stock upon conversion of any shares of the Company's Series A
              Preferred Stock; (y) the issuance of Class A Common Stock upon the
              exercise of any options, warrants or other rights to purchase
              Class A Common Stock outstanding on the date of the first issuance
              of the Company's Series A Preferred Stock, including this Warrant
              or (z) the future issuance of Class A Common Stock or warrants,
              options or rights to purchase such Class A Common Stock to
              employees, consultants, directors or vendors directly or pursuant
              to plans approved by the Board of Directors so long as such
              options are granted at fair market value.

     (i)  AMENDMENTS.  Neither  the  Warrant nor any term hereof may be changed,
waived,  discharged  or  terminated  without  the prior  written  consent of the
Holder.

     (j) NO IMPAIRMENT. The Company will not avoid or seek to avoid the
observance or performance of any of the terms to be observed or performed
hereunder by the Company, but will at all times in good faith assist in the
carrying out of all the provisions of this Warrant and in the taking of all such
action as may be necessary or appropriate in order to protect the rights of any
Holder.

     (k) GOVERNING LAW. This Agreement  shall be governed by and construed under
the laws of the State of Florida.

     (l)  NOTICES.  All notices and other  communications  required or permitted
hereunder  shall be in writing and shall be mailed by first class mail,  postage
prepaid, addressed (a) if to the Holder, to Alex. Brown & Sons Incorporated, One
South Street,  Baltimore,  Maryland 21202, Attention:  Donald D. Notman, Jr., or
(b) if to the Company,  to or at such other address as to the Company shall have
furnished to the Holder in writing.

     IN WITNESS WHEREOF, SBA Communications  Corporation has caused this Warrant
to be executed by its officer hereunto duly authorized.


Dated:  March 6, 1997                       SBA Communications Corporation


                                            By: /s/ Steven E. Bernstein
                                               -----------------------------
                                                     Name: Steven E. Bernstein
                                                     Title: President

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                                  PURCHASE FORM
                                  -------------

                                                   Dated____________, 19_


         The undersigned hereby irrevocably elects to exercise its rights
pursuant to this Warrant to the extent of purchasing ________ shares of Class A
Common Stock of SBA Communications Corporation, and hereby makes payment of
$_________, in cash, in payment of the exercise price thereof.

         [The  undersigned  hereby  irrevocably  elects to  exercise  its rights
pursuant to this  Warrant to the extent of  purchasing  shares of Class A Common
Stock and hereby  authorizes  you to deliver such shares of Class A Common Stock
for sale to , and to  retain  from the  proceeds  of such  sale $ , in cash,  in
payment  of the  exercise  price  thereof  and to remit to the  undersigned  the
balance of such proceeds.]


                       INSTRUCTIONS FOR ISSUANCE OF STOCK

Name________________________________________________________________
         (Please typewrite or print in block letters)

Address______________________________________________________________

Signature_____________________________________________________________


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                                 ASSIGNMENT FORM
                                 ---------------

         FOR VALUE RECEIVED, hereby sells, assigns and transfers unto
Name_____________________________________________________________________
         (Please typewrite or print in block letters)

Address__________________________________________________________________

the right to purchase Class A Common Stock of SBA Communications Corporation
(the "Company"), represented by this Warrant to the extent of ___________ shares
as to which such right is exercisable and does hereby irrevocably constitute and
appoint ______________ as Attorney, to transfer the same on the books of the
Company with full power of substitution in the premises.

Date _________, 1997

Signature ________________________


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