Aon Center (Chicago) Aon Center (Chicago) The Aon Center (200 East Randolph Street, formerly Amoco Building) is a modern supertall skyscraper in the Chicago Loop, Chicago, Illinois, United States, designed by architect firms Edward Durell Stone and The Perkins and Will partnership, and completed in 1974 as the Standard Oil Building. With 83 floors and a height of 1,136 feet (346 m), it is the third tallest building in Chicago, surpassed in height by the Willis Tower, and the Trump International Hotel and Tower. The building is managed by Jones Lang LaSalle, which is also headquartered in the building. Aon Center formerly had
Randolph Tower Randolph Tower Randolph Tower, formerly known as the Steuben Club Building, is a historic Gothic Revival skyscraper in Downtown Chicago. The building was constructed in 1929 and designed by architect Karl M. Vitzthum, who designed another Chicago landmark, the historic One North LaSalle Building. Randolph Tower was built for the Steuben Club of Chicago to promote German-American heritage. After the first World War, American citizens of German descent sought to found clubs to serve as a testimonial of their loyalty to the ideals of American citizenship. The first 25 floors were built for retail and offices and the club was