London ⁱ/ˈlʌndən/ is the capital city of England and the United Kingdom, the largest metropolitan area in the United Kingdom, and the largest urban zone in the European Union by most measures. Located 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. London's ancient core, the City of London, largely retains its square-mile mediaeval boundaries. Since at least the 19th century, the name London has also referred to the metropolis developed around this core. The bulk of this conurbation forms the London region and the Greater London administrative area, governed by the elected Mayor of London and the London Assembly.

London is a leading global city, with strengths in the arts, commerce, education, entertainment, fashion, finance, healthcare, media, professional services, research and development, tourism and transport all contributing to its prominence. It is the world's leading financial centre alongside New York City and has the fifth-largest city GDP in the world (and the largest in Europe). London has been described as a world cultural capital. It was the world's most visited city during 2011 and London Heathrow is the world's busiest airport by number of international passengers. London's 43 universities form the largest concentration of higher education in Europe. In 2012 London will become the first city to host the modern Summer Olympic Games three times.

North London is the northern part of London, England. It is an imprecise description and the area it covers is defined differently for a range of purposes. Common to these definitions is that it includes districts located north of the River Thames and is used in comparison with South London. However, it is also often used in comparisons with Central London, East London and West London.

The River Thames divides Greater London into two parts. The northern part includes most of the historic central areas including the City, the East End and the West End; and the majority of the London Underground network.

This area is made up of the City of London and the London boroughs of Barking and Dagenham, Barnet, Brent, Camden, Ealing, Enfield, Hackney, Hammersmith and Fulham, Haringey, Harrow, Havering, Hillingdon, Hounslow, Islington, Kensington and Chelsea, Newham, Redbridge, Tower Hamlets, Waltham Forest, and Westminster. This definition is used by the Boundary Commission for England. The London Borough of Richmond upon Thames includes sections on both sides of the River Thames. The boundary commission class the entire district as part of South London.