London is the capital and largest urban area of England and the United Kingdom. At its core, the ancient City of London, to which the name historically belongs, still retains its limited mediaeval boundaries; but since at least the 19th century the name "London" has also referred to the whole metropolis which has developed around it.

London has an official population of 7,512,400 (as of mid-2006) within the boundaries of Greater London and is the most populous municipality in the European Union. The urban area of London extends beyond the limits of Greater London and has a population of 8,278,251 (as of 2001). The metropolitan area is estimated to have a population of between 12 and 14 million. London's diverse population draws from a wide range of peoples, cultures, and religions, and over 300 different languages are spoken within the city. It is an international transport hub, with five major international airports serving the area and a large port. It serves as the largest aviation hub in the world, and the multi-terminal Heathrow Airport carries more international passengers than any other airport in the world.