Chicago Midway International Airport , typically referred to as Midway Airport, Chicago Midway, or simply Midway, is a major commercial airport on the Southwest side of Chicago, Illinois, located approximately 12 miles (19 km) from the Loop business district. Established in 1927, Midway served as Chicago's primary airport until the opening of O'Hare International Airport in 1955. Today, Midway is one of the busiest airports in the nation and the second-busiest airport both in the Chicago metropolitan area and the state of Illinois, serving 20,844,860 passengers in 2019. Midway is a base for Southwest Airlines, which carries over 95% of the passengers at the airport. The airport's current name is in honor of the Battle of Midway. The now-defunct Midway Airlines that once serviced the airport took its name from the airport. The airfield is located in a square mile bounded by 55th and 63rd Streets, and Central and Cicero Avenues. The current terminal complex was completed in 2001. The terminal bridges Cicero Avenue and contains 43 gates with facilities for international passengers. The CTA rapid transit Orange Line provides transit to Downtown Chicago, where it connects with other subway/elevated rapid transit lines. History Early history (1923–1962) Originally named Chicago Air Park, Midway Airport was built on a plot in 1923 with one cinder runway mainly for airmail flights. In 1926 the city leased the airport and named it Chicago Municipal Airport on December 12, 1927. By 1928, the airport had twelve hangars and four runways, lit for night operations. A major fire early on June 25, 1930 destroyed two hangars and 27 aircraft, "12 of them tri-motor passenger planes." The loss was estimated at more than two million dollars. The hangars destroyed were belonged to the Universal Air Lines, Inc. and the Grey Goose Airlines, the latter under lease to Stout Air Lines. The fire followed an explosion of undetermined cause in the Universal hangar. In 1931 a new passenger terminal opened at 62nd St; the following year the airport claimed to be the "World's Busiest" with over 100,846 passengers on 60,947 flights. (The July 1932 Official Aviation Guide (OAG) shows 206 scheduled airline departures a week.) More construction was funded in part by $1 million from the Works Progress Administration; the airport expanded to fill the square mile in 1938–41 after a court ordered the Chicago and Western Indiana Railroad to reroute tracks that had crossed the square