The original airfield was established in 1920 as Hamilton Airport by local business owner and aviator, Thomas F. Hamilton. Milwaukee County purchased the land on October 19, 1926 and renamed the airport Milwaukee County Airport. The first airport terminal there, the Hirschbuehl Farmhouse, opened in July 1927. That month, Northwest Airlines, Inc., began air service from Milwaukee to Chicago and Minneapolis/St. Paul. In August 1927, world-renowned aviator Charles Lindbergh visited the Milwaukee airport. Kohler Aviation Corporation began providing passenger service across Lake Michigan on August 31, 1929.