As filed with the Securities and Exchange Commission on July 12, 2000
                                             Registration No. 333-
===============================================================================

                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549
                                 --------------


                                    FORM S-8
                             REGISTRATION STATEMENT
                                      UNDER
                           THE SECURITIES ACT OF 1933
                                  ------------


                           AMERICAN TOWER CORPORATION
             (Exact Name of Registrant as Specified in Its Charter)

            Delaware                                 65-0723837
(State or Other Jurisdiction of                    (I.R.S. Employer
 Incorporation or Organization)                   Identification No.)




               116 Huntington Avenue, Boston, Massachusetts 02116
                                 (617) 375-7500
           (Address of Principal Executive Offices including zip code)
                                  -------------

                       American Tower Systems Corporation
                             1997 Stock Option Plan
                            (Full titles of the plan)
                                  ------------

                                 Steven B. Dodge
                            Chairman of the Board of
                      Directors and Chief Executive Officer
                           American Tower Corporation
                              116 Huntington Avenue
                           Boston, Massachusetts 02116
                                 (617) 375-7500
            (Name, address and telephone number of Agent For Service)
                                  -------------

                                    Copy to:
                             Norman A. Bikales, Esq.
                            Sullivan & Worcester LLP
                             One Post Office Square
                           Boston, Massachusetts 02109
                                 (617) 338-2800
                                ----------------

If, as a result of stock splits,  stock dividends or similar  transactions,  the
number of securities  purported to be registered on this Registration  Statement
changes, the provisions of Rule 416 shall apply to this Registration Statement.

The prospectus included in this Registration  Statement is a combined prospectus
which also relates to 15,000,000  shares of common stock  previously  registered
under the Company's  registration statement on Form S-8 dated April 28, 1998 and
filed on May 6, 1998 (file no. 333-51959).

CALCULATION OF REGISTRATION FEE Proposed Proposed Maximum Title of Securities Amount to be Maximum Offering Aggregate Amount of to be Registered Registered Price Per Share(1) Offering Price(1) Registration Fee ---------------- ---------- ------------------ ----------------- ---------------- Class A Common Stock, par value $.01 per share 9,000,000 $43.53125 $391,781,250 $103,430.25 (1) The proposed maximum offering price per share and the proposed maximum aggregate offering price have been estimated solely for purpose of calculating the amount of the registration fee in accordance with Rules 457(c) and 457(h) under the Securities Act of 1933, as amended, on the basis of the average of the high and low prices of the Class A Common Stock on the New York Stock Exchange on July 7, 2000. A registration fee of $81,460 was paid upon the filing of the prior registration statement.

PART I - INFORMATION REQUIRED IN THE SECTION 10(a) PROSPECTUS Item 1. Plan Information; Item 2. Registrant Information and Employee Plan Annual Information. The documents containing the information required by these items will be given to employees participating in the American Tower Systems Corporation 1997 Stock Option Plan and are not required to be filed with the Securities and Exchange Commission (the "Commission") as part of the registration statement or as an exhibit thereto. Employees participating in the Plan may obtain, without charge, a copy of the Plan or the documents set forth in Item 3, below, by request to Ms. Anne Alter, Director of Investor Relations, American Tower Corporation, 116 Huntington Avenue, Boston, Massachusetts 02116 ((617) 375-7500). PART II - INFORMATION REQUIRED IN THE REGISTRATION STATEMENT Insofar as additional securities are being registered of the same class as other securities for which a registration statement filed on this form relating to an employee benefit plan is effective, in accordance with General Instruction E to the Registration Statement on Form S-8, American Tower Corporation (the "Company") hereby incorporates by reference the contents of the Company's Registration Statement on Form S-8 dated April 28, 1998 and filed on May 6, 1998 (file no. 333-51959) and omits the information required by Part II from this registration statement, other than Item 3, Item 5 and Item 8 below, which have been updated. Item 3. Incorporation of Documents by Reference. The Company previously registered under the Securities Act of 1933 an aggregate of 15,000,000 shares of common stock offered pursuant to the American Tower Systems Corporation 1997 Stock Option Plan pursuant to a registration statement on Form S-8 (file no. 333-51959) dated April 28, 1998 and filed with the Commission on May 6, 1998, which is incorporated in this registration statement by reference. The following additional documents, which have been filed by the Company with the Commission, are incorporated by reference in and made a part of this registration statement, as of their respective dates: (a) The Company's Annual Report on Form 10-K for the fiscal year ended December 31, 1999; (b) The Company's Quarterly Report on Form 10-Q for the quarter ended March 31, 2000; (c) The Company's Current Reports on Form 8-K dated January 28, 2000, January 31, 2000, February 9, 2000, February 24, 2000, March 14, 2000, March 30, 2000, April 13, 2000, May 15, 2000, May 23, 2000, June 12, 2000, June 23, 2000 and June 29, 2000; and (d) The description of the Common Stock contained in the Company's registration statement on Form 8-A filed on June 4, 1998. All documents subsequently filed by the Company pursuant to Sections 13(a), 13(c), 14 and 15(d) of the Securities Exchange Act of 1934, as amended, prior to the filing of a post-effective amendment which indicates that all securities offered have been sold or which deregisters all securities then remaining unsold, shall be deemed to be incorporated by reference in this registration statement and to be part hereof from the date of filing of such documents. Any statement contained in a document incorporated or deemed to be incorporated by reference herein shall be deemed to be modified or superseded for purposes of this registration statement to the extent that a statement herein, or in any subsequently filed document which also is or is deemed to be incorporated by reference, modifies or supersedes such statement. Any statement so modified or superseded shall not be deemed, except as so modified or superseded, to constitute a part of this registration statement. II-1

Item 5. Interests of Named Experts and Counsel. The validity of the shares offered hereby will be passed upon for the Company by Sullivan & Worcester LLP, Boston, Massachusetts. As of June 1, 2000, Norman A. Bikales, a member of the firm of Sullivan & Worcester LLP, owned 11,000 shares of our Class A common stock and 41,490 shares of Class B common stock and had options to purchase 20,000 shares of Class A common stock at $10.00 per share and 25,000 shares of Class A common stock at $23.813 per share. Mr. Bikales and other partners and associates of that firm serve as secretary or assistant secretaries for us and certain of our subsidiaries. Item 8. Exhibits. EXHIBIT INDEX Exhibit No. Description 5.1 Opinion of Sullivan & Worcester LLP.* 23.1 Consent of Sullivan & Worcester LLP (contained in the opinion of Sullivan & Worcester LLP filed herewith as Exhibit 5.1). 23.2 Consent of Deloitte & Touche LLP.* 23.3 Consent of KPMG LLP.* 23.4 Consent of KPMG LLP.* 24 Power of Attorney (included in signature page of this Registration Statement). *Filed herewith. II-2

SIGNATURES Pursuant to the requirements of the Securities Act of 1933, the Company certifies that it has reasonable grounds to believe that it meets all of the requirements for filing on Form S-8 and has duly caused this registration statement to be signed on its behalf by the undersigned, thereunto duly authorized, in the City of Boston, Commonwealth of Massachusetts, on this 12th day of July, 2000. AMERICAN TOWER CORPORATION By: /s/ Steven B. Dodge Steven B. Dodge Chairman of the Board, President and Chief Executive Officer The undersigned Officers and Directors of the Company hereby severally constitute Steven B. Dodge, Joseph L. Winn and Jonathan R. Black, and each of them acting singly, our true and lawful attorneys to sign for us and in our names in the capacities indicated below any amendments to this registration statement on Form S-8 (including any post-effective amendments hereto) and to file the same, with Exhibits thereto and other documents in connection therewith, with the Commission, granting unto each of said attorneys, acting singly, full power and authority to do and perform each and every act and thing requisite or necessary to be done in and about the premises, as fully to all intents and purposes as he might or could do in person, hereby ratifying and confirming our signatures to said amendments to this registration statement signed by our said attorneys and all else that said attorneys may lawfully do and cause to be done by virtue hereof. Pursuant to the requirements of the Securities Act of 1933, this registration statement has been signed below by the following persons on behalf of the Company in the capacities indicated on the 11th day of July, 2000. Signatures Title /s/ Steven B. Dodge Steven B. Dodge Chairman, President and Chief Executive Officer /s/ Alan L. Box Alan L. Box Executive Vice President and Director /s/ Joseph L. Winn Joseph L. Winn Chief Financial Officer and Treasurer /s/ Justin D. Benincasa Justin D. Benincasa Vice President and Corporate Controller /s/ Arnold L. Chavkin Arnold L. Chavkin Director /s/ Dean H. Eisner Dean H. Eisner Director

/s/ Jack D. Furst Jack D. Furst Director /s/ J. Michael Gearon, Jr. J. Michael Gearon, Jr. Executive Vice President and Director Fred R. Lummis Director Randall T. Mays Director Thomas H. Stoner Director /s/ Maggie Wilderotter Maggie Wilderotter Director


                                                                    EXHIBIT 5.1


                              SULLIVAN & WORCESTER LLP
                               ONE POST OFFICE SQUARE
                             BOSTON, MASSACHUSETTS 02109
                                   (617) 338-2800
                                FAX NO. 617-338-2880
     IN WASHINGTON, D.C.                                   IN NEW YORK CITY
1025 CONNECTICUT AVENUE, N.W.                              767 THIRD AVENUE
   WASHINGTON, D.C. 20036                              NEW YORK, NEW YORK 10017
       (202) 775-8190                                       (212) 486-8200
    FAX NO. 202-293-2275                                 FAX NO. 212-758-2151





                                            July 12, 2000


American Tower Corporation
116 Huntington Avenue
Boston, MA  02116

         Re:      Registration of Stock Option Plan Amendment on Form S-8

Ladies and Gentlemen:

         In connection with the  registration  under the Securities Act of 1933,
as amended (the "Act"), by American Tower  Corporation,  a Delaware  corporation
(the "Company"), of 9,000,000 shares of its Class A Common Stock, par value $.01
per share ("Common  Stock"),  that are to be offered under and are issuable upon
the exercise of options granted and to be granted  pursuant to the provisions of
the American Tower Systems Corporation 1997 Stock Option Plan (the "Stock Option
Plan") (all such shares shall be referred to herein as the "Registered Shares"),
the following  opinion is furnished to you to be filed with the  Securities  and
Exchange   Commission  (the  "Commission")  as  Exhibit  5.1  to  the  Company's
registration statement on Form S-8 (the "Registration Statement") under the Act.

         We have  acted  as  counsel  to the  Company  in  connection  with  the
Registration Statement,  and we have examined originals or copies,  certified or
otherwise  identified to our satisfaction,  of the Registration  Statement,  the
Restated  Articles of  Incorporation  of the  Company,  as  presently in effect,
corporate records of the Company, and such other documents as we have considered
necessary in order to furnish the opinion hereinafter set forth.

         We  express no  opinion  herein as to any laws other than the  Delaware
General Corporation Law and the federal law of the United States, and we express
no opinion as to state securities or blue sky laws.

         Based on and subject to the foregoing, we are of the opinion that, when
issued in  accordance  with the terms of the Stock  Option  Plan and the options
granted  thereunder,  the  Registered  Shares will be duly  authorized,  validly
issued, fully paid and nonassessable by the Company.

         We hereby  consent to the  filing of this  opinion as an exhibit to the
Registration  Statement  and to the  reference  to our  firm  in the  Prospectus
forming a part of the Registration Statement.



American Tower Corporation July 12, 2000 Page 2 In giving such consent, we do not thereby admit that we come within the category of persons whose consent is required under Section 7 of the Act or the rules and regulations of the Commission promulgated thereunder. Very truly yours, /s/ SULLIVAN & WORCESTER LLP


                                                                   EXHIBIT 23.2




                          INDEPENDENT AUDITORS' CONSENT

     We consent to the incorporation by reference in this Registration Statement
of American  Tower  Corporation  on Form S-8 of our report  dated March 1, 2000,
appearing in the Annual Report on Form 10-K of American  Tower  Corporation  for
the year ended December 31, 1999.




                                               /S/ DELOITTE & TOUCHE LLP
Boston, Massachusetts
July 10, 2000


                                                                EXHIBIT 23.3

                       CONSENT OF INDEPENDENT ACCOUNTANTS

The Board of Directors
UNIsite, Inc. and Subsidiaries:

     We consent to the incorporation by reference in the registration  statement
on Form S-8 of American Tower  Corporation of our report dated January 14, 2000,
with  respect  to  the  consolidated   balance  sheets  of  UNIsite,   Inc.  and
Subsidiaries  as of  December  31, 1999 and 1998,  and the related  consolidated
statements  of   operations,   redeemable   convertible   preferred   stock  and
stockholders'  deficit,  and cash flows for each of the years in the  three-year
period ended  December 31, 1999 which report appears in the Form 8-K of American
Tower Corporation dated March 30, 2000.


                                              /s/ KPMG LLP

Tampa, Florida
July 10, 2000


                                                                 EXHIBIT 23.4

                       CONSENT OF INDEPENDENT ACCOUNTANTS

The Board of Directors
ICG Satellite Services, Inc.

     We consent to the incorporation by reference in the registration  statement
on Form S-8 for the 1997 Stock Option Plan of American Tower  Corporation of our
report dated February 28, 2000, with respect to the  consolidated  balance sheet
of ICG Satellite Services,  Inc. and subsidiary as of November 30, 1999, and the
related  consolidated  statements of operations and accumulated deficit and cash
flows for the eleven-month  period ended November 30, 1999, which report appears
in the Form 8-K of American Tower Corporation dated March 30, 2000.

                                                 /s/ KPMG LLP
Denver, Colorado
July 10, 2000