17. Midway Airport
Prior to the end of the First World War, most of the intercity mail ran on railroads. Many trains included Post Office cars, which processed, postmarked, and delivered mail to stations on their routes. Before the war experiments using airplanes to deliver mail created a novelty and a new term – airmail – entered the English language. Nonetheless, the advances in aviation before the war did not support the wide use of airmail, as airplanes simply couldn’t carry very large loads. Aircraft technology advanced rapidly during and after the war, and barnstorming pilots began to supplement their incomes by carrying mail both privately and for the United States Post Office.
Regularly scheduled airmail service in the United States began in May, 1918. In order to include Chicago in the new service, the city needed an airfield. In 1923 the city designated a 320-acre site as the Chicago Air Park. It leased the site three years later, naming it Chicago Municipal Airport. Originally equipped with a single, cinder-paved runway, by 1930 it had four runways, 12 hangars, and over two dozen airplanes. By 1931, when a new passenger terminal opened, the airport staked the claim of being the busiest in the world, operating more than 60,000 flights that year, carrying over 100,000 passengers. La Guardia surpassed it in the claim for the world’s busiest airport in the 1930s, though Midway (renamed for the World War II battle) reclaimed the title in 1948, and kept it for the ensuing dozen years running.