London is the capital city of England and the United Kingdom. An important settlement for around two millennia, London is today one of the world's leading business, financial and cultural centres, and its influence in politics, education, entertainment, media, fashion and the arts all contribute to its status as one of the major global cities.

London is the most populous city within city limits in the European Union with an official population of 7.6 million (as of 2006) and has a metropolitan area population of between 12 and 14 million people. Its population is very cosmopolitan, drawing from a wide range of peoples, cultures and religions, speaking over 300 different languages. London is an international transport hub, with five international airports and a large port. It serves as the largest aviation hub in the world, and its main airport, the multi terminal Heathrow, carries more international passengers than any other airport in the world.

London is a major tourist destination, with four world heritage sites and numerous iconic landmarks such as the Houses of Parliament, Tower Bridge, the Tower of London, Westminster Abbey, Buckingham Palace and the London Eye amongst its many attractions, along with famous institutions such as the British Museum and the National Gallery.

Greater London covers an area of 609 square miles (1,579 km²), making it one of the world's largest cities by area. Its primary geographical feature is the Thames, a navigable river which crosses the city from the southwest to the east. The Thames Valley is a floodplain surrounded by gently rolling hills such as Parliament Hill, Addington Hills, and Primrose Hill. These hills presented no significant obstacle to the growth of London from its origins as a port on the north side of the river, and therefore London is roughly circular.