Chicago the skyscraper era, which would then be followed by many other cities around the world. Today, Chicago's skyline is among the world's tallest and densest. Some of the United States' tallest towers are located in Chicago; Willis Tower (formerly Sears Tower) is the second tallest building in the Western Hemisphere after One World Trade Center, and Trump International Hotel and Tower is the third tallest in the country. The Loop's historic buildings include the Chicago Board of Trade Building, the Fine Arts Building, 35 East Wacker, and the Chicago Building, 860-880 Lake Shore Drive Apartments by Mies van der Rohe.
Center City Tower (Philadelphia) Center City Tower (Philadelphia) Center City Tower was the working name of a formerly proposed skyscraper in downtown Philadelphia. Designed and proposed by the firm now known as KlingStubbins (designers of Philadelphia's Penn Center and Bell Atlantic Tower), the building would have risen to a height of 1,050 feet (320 m) and 75 stories, making it the tallest building in The United States outside New York and Chicago, surpassing the height of the Bank of America Plaza in Atlanta. With a floor area of , it is one of the largest in Center City. The building was designed with an