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
Sears, Roebuck and Company Complex a modillioned cornice. It housed water tanks for firefighting on the upper levels, as well as offices and secretarial training facilities. It also housed the early broadcast facilities for WLS-AM. In 2015, it was refurbished and reopened to the public as the "John D. and Alexandra C. Nichols Tower". It now houses non-profit groups and offices, including a classroom on the 12th floor for the School of the Art Institute of Chicago. The Sears Roebuck plaque is still visible on top of the building. The Sears, Roebuck and Company Administration Building is a broad five-story masonry building, occupying about 3/4