The Aon Center, completed in 1973 as the Standard Oil Building, has 83 floors and a height of 1,136 feet. It reigned as the second tallest building until January 2009 when it was surpassed by the addition of a spire to Trump Tower.
To really appreciate the Aon Center, you have to walk right up to it and crane your neck to see the top. Fortunately, this is possible thanks to a sunken plaza in front of the building with some rather extensive fountain work.
Donald Trump announced in 2001 that his Chicago skyscraper would become the tallest building in the world, but after the September 11,2001 attacks, the building plans were scaled back and they’ve settled on 2nd tallest in the U.S. The building will, however, break the record for the world's highest residence which has been held since 1969by the John Hancock Center.
Trump Tower sits at 401 North Wabash Avenue in the River North District. The building occupies the site vacated by the Chicago Sun-Times, one of the city's two major newspapers and is a block away from the southern end of the Magnificent Mile portion of Michigan Avenue. The restaurant on the 16th floor has a clear view of the Chicago River's entrance to Lake Michigan.