Aon Center (Chicago)

Aon Center is a skyscraper in Chicago, United States. It is 346 meters (1,136 feet) tall and has 83 floors. It was built in 1973 and is one of the tallest buildings in the world and the third tallest in Chicago.
At first it was named the Standard Oil Building, but when the name of the company changed in 1985 it became the Amoco Building. The building was sold and became the Aon Center in 1999.