Aon Center (Chicago) the world headquarters of Aon and Amoco. Aon's US operations are still headquartered here. The building is also the co-headquarters of Kraft Heinz. The Standard Oil Building was constructed as the new headquarters of the Standard Oil Company of Indiana, which had previously been housed at South Michigan Avenue and East 9th Street. When it was completed in 1973, it was the tallest building in Chicago and the fourth-tallest in the world, earning it the nickname "Big Stan". (A year later, the Sears Tower took the title as Chicago's and world's tallest.) The building employs a tubular steel-framed structural system
Tower Petroleum Building Tower Petroleum Building The Tower Petroleum Building (also known as The Tower Building) is a historic Art Deco Skyscraper located at 1907 Elm Street in the City Center District of Downtown Dallas. The tower, a contributing property in the Dallas Downtown Historic District and the Harwood Street Historic District, features Zig-zag Moderne styling and was designed by architect Mark Lemmon. The Tower Petroleum Building features Zig-zag Moderne motifs, one of the few buildings left in Downtown Dallas which features such designs. The building's facade is clad in limestone and has green spandrels panels between the windows. The upper floors of