London is the capital and largest city of England and the United Kingdom. Located in southeast England on the River Thames, it sits at the head of a 50-mile tidal estuary leading to the North Sea. As of 2024, the city has a population of 9.1 million people, while its wider metropolitan area is the largest in Western Europe with a population of 15.4 million.
The city has served as a major settlement for nearly 2,000 years. Its ancient core and financial center, known as the City of London, was founded by the Romans as Londinium and maintains its medieval boundaries. To the west lies the City of Westminster, which has hosted the national government and parliament for centuries. Since 1965, the metropolis has largely comprised the administrative area of Greater London, governed by the Greater London Authority and 33 local authorities.