The Sears Tower is a skyscraper in Chicago, Illinois, and the tallest building in the United States, by the measurement from the ground to its roof. By the measurement to the top of the antenna/spire, One World Trade Center passed it by 58 cm (1.9 ft) until only days before it was destroyed on September 11th, 2001, a short extension being installed on one of Sears' antennas in early September of that year. Commissioned by Sears, Roebuck and Company, it was designed by chief architect Bruce Graham and structural engineers Srinivasa "Hal" Iyengar and Fazlur Khan of Skidmore, Owings & Merrill Reference |