London (England), city, capital of the United Kingdom. It is situated in south-eastern England at the head of the River Thames estuary. Settled by the Romans as an important shipping point for crops and minerals, it gradually developed into the wealthy capital of a thriving industrial and agricultural nation. The expansion in the 19th century of the British Empire increased London's influence still further. Since World War II the city's prominence on the international stage has diminished, but it remains a flourishing financial centre and home to one of the world's most important stock exchanges., Havering, Hillingdon, Hounslow, Kingston upon Thames, Merton, Redbridge, Richmond upon Thames, Sutton, and Waltham Forest. Transport Transport is essential to the operation of a city such as London. Its very development was significantly affected by the advent of the railways, and more recently the construction of roads (particularly the orbital M25 motorway) has influenced patterns of settlement and economic activity. London has one of the most extensive urban railway systems in the world; in addition to the Underground railway, there is a network of suburban railways covering London and the surrounding region. Most of the passenger-carrying Underground lines in central London were built before 1914. Suburban extensions were added before and after World War II. The most recent line, the Jubilee, opened in 1979 and in the 1990s was extended eastward to Stratford. The Docklands Light Railway connects the City of London with Docklands and other east London destinations. Most travel is done by rail and Underground, although there is also considerable commuting by car, particularly in the outer boroughs. London has about 18,000 licensed taxis. Railway services from London to Paris or Brussels through the Channel Tunnel run from the terminal at Waterloo station. London has three main airports. Heathrow, about 25 km (15 mi) west of London, is the world's busiest airport for international passengers and is Britain's most important airport for passengers and air freight (handling about 55 million passengers and over 1 million tonnes of freight in 1996). Gatwick (south of London) is Britain's second-busiest airport in terms of passenger traffic, and Stansted (to the north-east, in Essex) is the sixth-busiest. London City Airport based in the rejuvenated Docklands area, links Docklands and the City to continental Europe. The Port of London, covering about 150 km (93 mi) of waterway along the Thames to the east coast, is the largest port in Britain in terms of total tonnage of cargo handled and in terms of non-fuel traffic. The total tonnage handled in 1995 was about 52 million tonnes. Museums and Art Galleries London's museums and art galleries contain some of the most comprehensive collections of objects of artistic, archaeological, scientific, historical, and general interest. The British Museum in Bloomsbury is one of the biggest and most famous museums in the world. Its collections range from Egyptian and Classical antiquities through Saxon treasures to more recent artefacts.