Wrigley Building

The Wrigley Building (400-410 North Michigan Avenue, Near North Side, Chicago, Illinois) is a skyscraper in Chicago. It is directly across Michigan Avenue from the Tribune Tower on the Magnificent Mile. 
It was built to hold the corporate headquarters of the Wrigley Company. Construction began for the building in 1920. The building was Chicago's first air-conditioned office building.
The Wrigley Building was sold in 2011 to a group of investors that includes Zeller Realty Group and Groupon co-founders Eric Lefkofsky and Brad Keywell.