London is the capital city of England and the United Kingdom.[5] It is the most populous region, urban zone and metropolitan area in the United Kingdom. Standing on the River Thames, London has been a major settlement for two millennia, its history going back to its founding by the Romans, who named it Londinium.[6] London's ancient core, the City of London, largely retains its 1.12-square-mile (2.9 km2) mediaeval boundaries and in 2011 had a resident population of 7,375, making it the smallest city in England. Since at least the 19th century, the term London has also referred to the metropolis developed around this core.[7] The bulk of this conurbation forms the London region[8] and the Greater London administrative area,[9][note 1] governed by the Mayor of London and the London Assembly.[10]
