Croydon Airport (former ICAO code: EGCR) was the UK's only international airport during the interwar period. It opened in 1920, located near Croydon, then part of Surrey. Built in a Neoclassical style, it was developed as Britain's main airport, handling more cargo, mail, and passengers than any other UK airport at the time. Innovations at the site included the world's first air traffic control and the first airport terminal. During World War II the airport was named RAF Croydon as its role changed to that of a fighter airfield during the Battle of Britain; and in 1943 RAF Transport Command was founded at the site, which used the airport to transport thousands of troops into and out of Europe.

After the Second World War, its role returned to civil aviation, but the role of London's primary international airport passed to London Heathrow Airport. Croydon Airport closed in 1959. It had been known under eight different names while it was active.

In 1978, the terminal building and Gate Lodge were granted protection as Grade II listed buildings. In May 2017, Historic England raised the status of the terminal building to Grade II*.