St. Louis Downtown Airport covers an area of 1,013 acres (410 ha) which contains three paved runways: 12R/30L measuring 7,001 x 100 ft. (2,133 x 30 m), 12L/30R measuring 5,301 x 75 ft. (1,616 x 23 m) and 5/23 measuring 2,799 x 75 ft. (853 x 23 m).
For the 12-month period ending September 30, 2005, the airport had 170,000 aircraft operations, an average of 465 per day: 97% general aviation, 2% air taxi and 1% military. At that time there were 281 aircraft based at this airport: 62% single-engine, 21% multi-engine, 12% jet and 5% helicopter.
The airport opened in 1929 as Curtiss-Steinberg Airport. In 1940 it was renamed Curtiss-Parks Airport, followed by Parks Metropolitan Airport later that same year.
Taken over by the United States Army Air Forces on 1 August 1939 as a basic (level 1) pilot training airfield. Assigned to USAAF Gulf Coast Training Center (later Central Flying Training Command). Parks Air College conducted contract basic flying training. Flying training was performed with Fairchild PT-19s as the primary trainer. Also had several PT-17 Stearmans and a few P-40 Warhawks assigned. Inactivated 12 March 1944 with the drawdown of AAFTC's pilot training program.
The airport closed in 1959 and reopened six years later as Bi-State Parks Airport. It was renamed St. Louis Downtown-Parks Airport in 1984 and received its current name in 1999. Today, it is the third busiest airport in Illinois.