Philadelphia, the largest city in the U.S. state of Pennsylvania, is home to 381 completed high-rises, 29 of which stand taller than . The tallest building in the city is currently the 57-story Comcast Center, which rises in Center City. Comcast Center is also the tallest building in Pennsylvania and the 19th-tallest building in the United States. The second-tallest building is One Liberty Place, which rises 61 floors and . One Liberty Place stood as the tallest building in Pennsylvania for over 20 years until the completion of Comcast Center in 2008. Overall, six of the ten tallest buildings in Pennsylvania are in Philadelphia, with the remainder being in Pittsburgh. Philadelphia is one of only five American cities with two or more completed buildings over tall.