The 548 ft (167 m) City Hall remained the tallest building in the city until 1987 when One Liberty Place was constructed. Numerous glass and granite skyscrapers were built in Philadelphia's Center City from the late 1980s onwards. In 2007, the Comcast Center surpassed One Liberty Place to become the city's tallest building. The Comcast Innovation and Technology Center is under construction in Center City and is planned to reach a height of 1,121 feet (342 meters); upon completion, the tower is expected to be the tallest skyscraper in the United States outside of New York City and Chicago.
What is the tallest building?
Comcast Center