what is the name of the old sears tower in chicago
Willis Tower The Willis Tower, built as and still commonly referred to as the Sears Tower, is a 110-story,[4] 1,450-foot (442.1 m) skyscraper in Chicago, Illinois.[3] At completion in 1973, it surpassed the World Trade Center towers in New York to become the tallest building in the world, a title it held for nearly 25 years; it remained the tallest building in the Western Hemisphere until the completion of a new building at the World Trade Center site in 2014. The building is considered a seminal achievement for its designer Fazlur Rahman Khan.[5] The Willis Tower is the second-tallest building in the United States and the Western hemisphere – and the 16th-tallest in the world. More than one million people visit its observation deck each year, making it one of Chicago's most-popular tourist destinations. The structure was renamed in 2009 by the Willis Group as part of its lease on a portion of the tower's space.
Comcast Technology Center The Comcast Technology Center is a skyscraper under construction in Center City, Philadelphia.[5][6] The 60-floor building, with a height of 1,121 feet (342 m), is the ninth-tallest building in the United States and the tallest outside Manhattan and Chicago. The tower is located on the southwest corner of 18th and Arch Streets, one block west of the Comcast Center, the headquarters of Comcast Corporation. A hotel—the highest in the country[7]—and restaurant will be located on the top floors, while central floors will contain offices for Comcast software developers and engineers, and the lowest floors will have television studios and retail stores.[8][9]