London is the capital and
largest city
The United Nations uses three definitions for what constitutes a city, as not all cities in all jurisdictions are classified using the same criteria. Cities may be defined as the cities proper, the extent of their urban area, or their metropo ...
of
England and the
United Kingdom, with a population of just under 9 million.
It stands on the
River Thames in south-east England at the head of a
estuary down to the
North Sea, and has been a major settlement for two millennia.
The
City of London, its ancient core and
financial centre
A financial centre ( BE), financial center ( AE), or financial hub, is a location with a concentration of participants in banking, asset management, insurance or financial markets with venues and supporting services for these activities to ta ...
, was founded by the
Romans as ''
Londinium
Londinium, also known as Roman London, was the capital of Roman Britain during most of the period of Roman rule. It was originally a settlement established on the current site of the City of London around AD 47–50. It sat at a key cross ...
'' and retains its medieval boundaries.
[See also: Independent city § National capitals] The
City of Westminster
The City of Westminster is a City status in the United Kingdom, city and London boroughs, borough in Inner London. It is the site of the United Kingdom's Houses of Parliament and much of the British government. It occupies a large area of cent ...
, to the west of the City of London, has for centuries hosted the national
government and
parliament. Since the 19th century,
the name "London" has also referred to the
metropolis around this core, historically split between the