London is the capital city of the United Kingdom.

London is also the largest city in England and the United Kingdom with a total population of 9,002,488. It stands on the River Thames in south-east England at the head of a 50-mile (80 km) estuary down to the North Sea and has been a major settlement for two millennia. The City of London, its ancient core and financial center, was founded by the Romans as Londinium and retains boundaries close to its medieval ones. Since the 19th century, "London" has also referred to the metropolis around this core, historically split between the counties of Middlesex, Essex, Surrey, Kent, and Hertfordshire, which largely comprises Greater London, governed by the Greater London Authority. The City of Westminster, to the west of the City of London, has for centuries held the national government and parliament.