Chicago Midway International Airport

The city leases the airfield, originally established in 1923 as Chicago Air Park, and formally names it Chicago Municipal Airport on December 12, 1927.

The airport claims the title of world's busiest, handling over 100,000 passengers on roughly 61,000 flights that year — a status it holds, with some fluctuation, into the late 1950s (surpassing LaGuardia in 1948 and peaking around 10 million passengers in 1959).

The airport is renamed Chicago Midway Airport in July 1949, commemorating the pivotal WWII Battle of Midway.

O'Hare International Airport opens with longer runways able to handle new four-engine jets like the Boeing 707, which Midway's shorter runways could not accommodate; Midway's traffic collapses through the early 1960s, briefly leaving only helicopter shuttle service as scheduled traffic in the early 1960s.

United Air Lines Flight 553 crashes on approach on December 8, killing 45 people, including Watergate figure Dorothy Hunt.

Southwest Airlines begins service at Midway, eventually growing to dominate the airport with over 90% of its traffic and driving its revival as a major low-cost hub.

A 900,000-square-foot terminal building with 43 gates opens to the public, the centerpiece of a Terminal Development Program launched in 1997, following the City of Chicago's 1982 purchase of the airport.

Southwest Airlines Flight 1248 skids off the runway during a snowstorm on landing, crossing into an adjacent roadway and killing a six-year-old child in a car; the accident prompted national scrutiny of runway safety margins at airports with short runways.