London is the capital of and largest city in England and the United Kingdom, with the largest municipal population in the European Union.[7][8] Standing on the River Thames in the south-east of England, at the head of its 50-mile (80 km) estuary leading to the North Sea, London has been a major settlement for two millennia. Londinium was founded by the Romans.[9] The City of London, London's ancient core − an area of just 1.12 square miles