EXHIBIT 10.125 

                       INCENTIVE STOCK OPTION AGREEMENT
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THIS AGREEMENT CERTIFIES THAT, for value received, MICHAEL N. SIMKIN the 
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"Optionee"), is entitled to purchase from SBA COMMUNICATIONS CORPORATION, a 

Florida Corporation (the "Company"), 200,000 shares of the Company's Class A 
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common stock (the "Common Stock"), subject to adjustment pursuant to Section 9
hereof, at the price of $2.63 per share (the Exercise Price").

1.   GRANT UNDER 1996 STOCK OPTION PLAN.  This option is granted pursuant to and
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     is governed by the Company's 1996 Stock Option Plan (the "Plan") and,
     unless the context otherwise requires, terms used herein shall have the
     same meaning as in the Plan. Determinations made in connection with this
     option pursuant to the Plan shall be governed by the Plan as it exists on
     this date. In the event of any inconsistency between this Agreement and the
     Plan, or if any issue is not addressed by this Agreement, the provisions of
     the Plan shall govern.

2.  GRANT AS INCENTIVE STOCK OPTION; OTHER OPTIONS.  The option right granted
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    under this Agreement shall be an "incentive stock option" as such term is
    defined in Section 422(b) of the Internal Revenue Code of 1986, as amended
    (the "Code"), and is intended to qualify as an incentive stock option under
    Section 422 of the Code. This option is in addition to any other options
    heretofore or hereafter granted to the Optionee by the Company.

3.  VESTING.  Subject to the terms, provisions and limitations contained in the
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    Plan, the option granted under this Agreement shall vest and become
    exercisable in three installments of 66666.67 shares each, with the first
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    installment to occur upon December 31, 1998, and with two subsequent
    vestings to occur on December 31, 1999 and December 31, 2000. Subject to any
    limitations contained in the Plan, this option may be exercised up to and
    including the date which is ten (10) years from June 15, 1998.

4.  PARTIAL EXERCISE.  Exercise of this option up to the extent above stated may
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    be made in part at any time and from time to time within the above limits,
    except that this option may not be exercised for a fraction of a share. Any
    fractional share with respect to which an installment of this option cannot
    be exercised because of the limitation contained in the preceding sentence
    shall remain subject to this option and shall be available for later
    purchase by the Optionee in accordance with the terms hereof.

5.  PAYMENT OF PRICE.  The Exercise Price is payable in cash and/or shares of
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    Stock (as such term is defined in the Plan) valued at its Fair Market Value
    at the time the option is exercised, or, in the discretion of the
    Compensation Committee of the Company's Board of Directors, either (i) in
    other property having a Fair Market Value on the date of exercise equal to
    the option price, or (ii) by delivering to the Company a copy of irrevocable
    instructions to a stockbroker to deliver promptly to the Company an amount
    of sale or loan proceeds sufficient to pay the Exercise Price.

6.  AGREEMENT TO PURCHASE FOR INVESTMENT.  By acceptance of this option, the
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    Optionee agrees that a purchase of shares under this option will not be made
    with a view of their distribution, as that term is used in the Securities
    Act of 1933, as amended (the "Act"), unless in the opinion of counsel to the
    Company such distribution is in compliance with or exempt from the
    registration and prospectus requirements of the Act, or a registration
    statement is in effect pursuant to the Act with respect to the shares, and
    the Optionee agrees to sign a certificate to such effect at the time of
    exercising this option and agrees that the certificate for the shares so
    purchased may be inscribed with a legend to ensure compliance with the Act.

7.  METHOD OF EXERCISING OPTION.  Subject to the terms and conditions of this
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    Agreement, this option may be exercised by written notice to the Company, at
    the principal executive office of the Company, or to such transfer agent as
    the Company shall designate. Such notice shall state the election to
    exercise an option and the number of shares in respect of which it is 

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                       INCENTIVE STOCK OPTION AGREEMENT
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     being exercised and shall be signed by the person or persons so exercising
     this option. Such notice shall be accompanied by payment of the full
     Exercise Price of such shares, and the Company shall deliver a certificate
     or certificates representing such shares as soon as practicable after such
     payment shall be received. The certificate or certificates for the shares
     as to which this option shall have been so exercised shall be registered in
     the name of the person or persons so exercising this option (or, if this
     option shall be exercised by the Optionee and if the Optionee shall so
     request in the notice exercising this option, shall be registered in the
     name of the Optionee and another person jointly, with right of
     survivorship) and shall be delivered as provided above to or upon the
     written order of the person or persons exercising this option. In the event
     this option shall be exercised by any person or persons other than the
     Optionee (if in compliance with the Plan), such notice shall be accompanied
     by appropriate proof of the right of such person or persons to exercise
     this option. All shares that shall be purchased upon the exercise of this
     option as provided herein shall be fully paid and non-assessable.

8.   NO OBLIGATION TO EXERCISE OPTION.  The grant and acceptance of this option
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     imposes no obligation on the Optionee to exercise the options.

9.   CAPITAL CHANGES AND BUSINESS SUCCESSIONS.  The Plan contains provisions
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     covering the treatment of options in a number of contingencies such as
     stock splits and mergers. Provisions in the Plan for adjustment with
     respect to stock subject to options and the related provisions with respect
     to successors to the business of the Company are hereby made applicable
     hereunder and are incorporated herein by reference.

10.  RESERVATION OF COMMON STOCK.  The Company will at all times reserve and
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     keep available for issuance upon the exercise of this Agreement such number
     of its authorized but unissued shares of Common Stock as will be sufficient
     to permit the exercise in full hereof, and upon such issuance such shares
     of Common Stock will be validly issued, fully paid and nonassessable.

11.  NO SHAREHOLDER RIGHTS OR OBLIGATION.  This agreement will not entitle the
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     Optionee (or subsequent holder of this Agreement) hereof to any voting
     rights or other rights as a shareholder of the Company. No provision of
     this Agreement will give rise to any obligation of the Optionee for the
     Exercise Price of Common Stock acquirable by exercise hereof or as a
     shareholder of the Company.

12.  ENTIRE AGREEMENT.  This Agreement and the Plan represent the entire
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     understanding and agreement between the parties with respect to the subject
     matter hereof, and supersedes all other negotiations, understandings and
     representations (if any) made by and between such parties.

13.  AMENDMENTS.  Except as expressly contemplated by the Plan, the provisions
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     of this Agreement may not be amended, supplemented, waived or changed
     orally, but only by a writing signed by the party as to whom enforcement of
     any such amendment, supplement, waiver or modification is sought and making
     specific reference to this Agreement.

14.  ASSIGNMENTS.  Except as otherwise provided herein, no party shall assign
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     his or its rights and/or obligations hereunder without the prior written
     consent of each other party to this Agreement.

15.  FURTHER ASSURANCES.  The parties hereby agree from time to time to execute
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     and deliver such further and other transfers, assignments and documents and
     do all matters and things which may be convenient or necessary to more
     effectively and completely carry out the intentions of this Agreement.

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                       INCENTIVE STOCK OPTION AGREEMENT
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16.  BINDING EFFECT.  All of the terms and provisions of this Agreement shall be
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     binding upon, to the benefit of, and be enforceable by the parties and
     their respective legal representatives, successors and permitted assigns,
     whether so expressed or not.

17.  NOTICES.  All notices, requests, consents and other communications required
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     or permitted under this Agreement shall be in writing (including electronic
     transmission) and shall be (as elected by the person giving such notice)
     hand delivered by messenger or courier service, electronically transmitted,
     or mailed (airmail if international) by registered or certified mail
     (postage prepaid), return receipt requested, addressed to:

If to Optionee:
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Michael N. Simkin
To be provided

If to the Company:
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SBA Communications Corporation
One Town Center Road, 3rd Floor
Boca Raton, Florida  33486
Attn:  Steven E. Bernstein

or to such other address as any party may designate by notice complying with the
terms of this Section.  Each such notice shall be deemed delivered (a) on the
date delivered if by personal delivery; (b) on the date of transmission with
confirmed answer back if by electronic transmission; and (c ) on the date upon
which the return receipt is signed or delivery is refused or the notice is
designated by the postal authorities as not deliverable, as the case may be, if
mailed.

18.  SURVIVAL.  All covenants, agreements, representations and warranties made
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     herein or otherwise made in writing by any party pursuant hereto shall
     survive the execution and delivery of this Agreement and the consummation
     of the transactions contemplated hereby.

19.  JURISDICTION AND VENUE.  The parties acknowledge that a substantial portion
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     of the negotiations and anticipated performance of this Agreement occurred
     or shall occur in Palm Beach County, Florida. Any civil action or legal
     proceeding arising out of or relating to this Agreement shall be brought in
     the courts of record of the State of Florida in Palm Beach County or the
     United States District Court, Southern District of Florida, West Palm Beach
     Division. Each party consents to the jurisdiction of such court in any such
     civil action or legal proceedings and waives any objection to the laying of
     venue of any such civil action or legal proceeding in such court. Service
     of any court paper may be effected on such party my mail, as provided in
     this Agreement, or in such other manner as may be provided under applicable
     laws, rules of procedure or local rules.

20.  ENFORCEMENT COSTS.  If any civil action, arbitration or other legal
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     proceeding is brought for the enforcement of this Agreement, or because of
     an alleged dispute, breach, default or misrepresentation in connection with
     any provision of this Agreement, the successful or prevailing party or
     parties shall be entitled to recover reasonable attorney's fees, sales and
     use taxes, court costs and all expenses even if not taxable as court costs
     (including, without limitation, all such fees, taxes, costs and expenses
     incident to arbitration, appellate, bankruptcy and post-judgment
     proceedings), incurred in that civil action, arbitration or legal
     proceeding, in addition to any other relief to which such party or parties
     may be entitled. Attorney's fees shall include, without limitation,
     paralegal fees, investigative fees, administrative costs, sales and use
     taxes and all other charges billed by the attorney to the prevailing party.

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                       INCENTIVE STOCK OPTION AGREEMENT
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21.  GOVERNING LAW.  This agreement and all transactions contemplated by this
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     Agreement shall be governed by, and construed and enforced in accordance
     with, the laws of the State of Florida.

22.  PROVISION OF DOCUMENTATION TO OPTIONEE.  By signing this Agreement the 
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     Optionee acknowledges receipt of a copy of this Agreement and a copy of the
     Company's 1996 Stock Option Plan.

IN WITNESS WHEREOF, the Company and the Optionee have caused this instrument to
be executed, and the Optionee whose signature appears below acknowledges
acceptance of an original copy of this Agreement.

Date of Grant as of June 15, 1998
Date of Agreement: June 15, 1998

SBA COMMUNICATIONS CORPORATION


By: /s/ Steven E. Bernstein 
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     Steven E. Bernstein, President


/s/ Michael N. Simkin
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Michael N. Simkin

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