London Heathrow Airport officially opened for civilian aviation on 31 May 1946, though its origins trace back further, to a small grass airfield established by Fairey Aviation near the hamlet of Heath Row in 1930. The British government requisitioned the land in 1944, and after the war ended, it was handed over to the Ministry of Civil Aviation. The first year of operation brought just 63,000 passengers through what was then a tented village of army surplus marquees along the Bath Road. Known simply as London Airport for its first two decades, it was renamed Heathrow in September 1966 to reduce confusion with Gatwick and Stansted.

The airport sits 14 miles west of central London in the borough of Hillingdon, and its layout reflects 80 years of incremental expansion. It operates 2 parallel east-west runways and 4 terminals, numbered 2 through 5 following the closure of Terminal 1 in 2015. The Central Terminal Area was designed by architect Sir Frederick Gibberd, whose plan introduced a centralised passenger complex accessed via a tunnel beneath the main runway. Terminal 5, which opened in March 2008, is the primary base for British Airways. Terminal 2, rebuilt and reopened as The Queen's Terminal in June 2014, serves Star Alliance carriers. The airport is the primary hub for both British Airways and Virgin Atlantic, with over 90 airlines serving more than 200 destinations.

Heathrow logged a record 84.5 million passengers in 2025, its busiest year to date, and holds its position as Europe's leading hub airport. It has also hosted defining moments in aviation history: British Airways launched Concorde service from LHR on 21 January 1976, and the supersonic aircraft made its final commercial arrival at the airport on 24 October 2003.