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 city's loop business district. Established in 1927, midway served as Chicago’s primary airport until the opening of O’Hare international airport in 1944. 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.