American Tower and Unefon Form Strategic Alliance.

Business/Technology Editors

BOSTON--(BUSINESS WIRE)--May 5, 2000

American Tower Corporation (NYSE:AMT) today announced the signing of a letter of intent with Unefon S.A. de C.V. ("Unefon"). The two have agreed to form a strategic alliance to build and operate communications towers throughout the country of Mexico. The five year agreement calls for Unefon to lease up to 450 sites by co-locating on existing American Tower sites or by leasing space on sites newly constructed by American Tower. Build-to-suit towers will be designed to accommodate future co-location demands.

Michael Gearon, Jr., Executive Vice President of American Tower stated, "Our agreement with Unefon extends American Tower's commitment to the Mexican market where we have established ourselves as the tower leader. Through this agreement, we have further positioned ourselves to capitalize on the strong wireless demand for tower sites in this growing market."

"This agreement will accelerate the rate at which Unefon is able to roll out its network while also reducing our capital expenditure. This is one of the elements that will allow us to establish our network in a more cost effective manner," said Adrian Steckel, the CEO of Unefon. "American Tower's technical expertise will ensure that the entire system meets the highest standards and ensures full coverage of our market areas."

Formation of the alliance is subject to completion of definitive agreements. While the parties anticipate that definitive agreements will be completed by the end of the second quarter, there is no assurance that the parties will enter into definitive agreements within or after this time frame.

Unefon S.A. de C.V. is Mexico's newest national telephone company. Unefon holds licenses to provide PCS telephony services throughout Mexico in the 1.9GHZ frequency range. Unefon is a 50-50 joint venture between the Saba family and TV Azteca (NYSE:TZA)(BMV:TVAZTCA), one of two broadcast television companies in Mexico. Unefon has long term contracts with TV Azteca for advertising and with Grupo Elektra (NYSE:EKT)(BMV:ELEKTRA), Mexico's largest specialty retailer, and an affiliated company, for distribution and antenna location.

American Tower is the leading independent owner operator and developer of broadcast and wireless communications sites in North America. Giving effect to pending transactions, American Tower operates over 10,400 sites in the United States, Mexico and Canada, including approximately 300 broadcast tower sites. Of the 10,400 sites, over 9,000 are owned or leased towers and approximately 1,400 are managed and lease/sublease sites. Based in Boston, American Tower has regional hub offices in Boston, Atlanta, Chicago, Houston, San Francisco and Mexico City. For more information about American Tower Corporation and ATC Teleports, please visit our web sites www.americantower.com and www.atcteleports.com.

This press release contains "forward-looking statements" concerning future expectations, plans or strategies that involve a number of risks and uncertainties. The Company wishes to caution readers that certain factors may have affected the Company's actual results and could cause results for subsequent periods to differ materially from those expressed in any forward-looking statement made by or on behalf of the Company. Such factors include, but are not limited to (i) substantial capital requirements and leverage principally as a consequence of its ongoing acquisitions and construction activities, (ii) dependence on demand for wireless communications, use of satellites for internet data transmission, and implementation of digital television, (iii) the success of the Company's tower construction program and (iv) the successful operational integration of the Company's business acquisitions. The Company undertakes no obligation to update forward-looking statements to reflect subsequently occurring events or circumstances.