London Heathrow Airport or Heathrow (IATA: LHR, ICAO: EGLL) is the principal airport for London. The United Kingdom's biggest airport, Heathrow is also Europe's busiest airport for passenger traffic, and handles more international passenger traffic than any other airport in the world.

Heathrow Airport is located in Hayes, which is in the London Borough of Hillingdon, 15 miles (24 km) west of Charing Cross in Central London. It has two parallel main runways running east-west and four terminals. The airport is the largest airport serving Greater London.

Terminal 5 is under construction and will open in March 2008. There are plans to redevelop or rebuild other terminals and add extra runways. Beginning in 2008 and finishing by 2012, the construction of Heathrow East will replace Terminal 2 and The Queens Building.