Heathrow opened for civil operations on January 1, 1946, on the site of the Fairey Great West Aerodrome, taking its name from Heath Row, the hamlet demolished to build it. The first passengers checked in inside army surplus tents beside the runway.
The permanent central terminal area arrived in 1955, and Heathrow grew into the world's busiest international airport, a title it held for decades. It became the home of British Airways and its predecessors. From 1976 to 2003 served as the home base of Concorde's supersonic transatlantic services.
Terminal 4 opened in 1986, and the vast Terminal 5, built for British Airways, followed in 2008 after the longest planning inquiry in British history. The Queen's Terminal, a rebuilt Terminal 2, opened in 2014, completing a modernization that saw the original Terminal 1 close.
Constrained to two runways while rivals expanded, Heathrow became a case study in scarcity: its slots trade for tens of millions of dollars. The debate over a third runway has run for a generation, with the UK government again backing expansion in 2025. It remains Europe's busiest airport by passengers.