A newThames Estuary Airporthas been proposed at various times since the 1970s. London's existing principal airports, Heathrow, Gatwick and Stansted, are all situated in locations that are sub-optimal in various ways, such as being too close to built-up areas or requiring aircraft to fly low over London.
In the case of Heathrow the growth of air traffic has meant that the airport is close to capacity and any further expansion would require the demolition of substantial parts of West London and an increase in noise and atmospheric pollution across the whole city. Several locations for a new airport have been proposed in the Thames Estuary, to the east of London.