London is the capital of England and the United Kingdom. It has been a major settlement for two millennia, and its history goes back to its founding by the Romans, when it was named Londinium.London's core, the ancient City of London, the 'square mile', retains its medieval boundaries. Since at least the nineteenth century, the name "London" has also referred to the metropolis developed around it.Today, the bulk of this conurbation forms the London region and the Greater London administrative area, with its own elected mayor and assembly.
London is a major global city[11][12] and one of the world's largest financial centres.[13][14][15][16] Central London is home to the headquarters of more than half of the UK's top 100 listed companies (the FTSE 100) and more than 100 of Europe's 500 largest. London's influence in politics, finance, education, entertainment, media, fashion, the arts and culture in general contributes to its global position. It is a major tourist destination for both domestic and overseas visitors. London hosted the 1908 and 1948 Summer Olympics and will host the 2012 Summer Olympics.[17]
London contains four World Heritage Sites: the Tower of London; the historic settlement of Greenwich; the Royal Botanic Gardens, Kew; and the site comprising the Palace of Westminster, Westminster Abbey and St. Margaret's Church.[18]
London has a wide range of peoples, cultures, and religions, and more than 300 languages are spoken within its boundaries.[19] In July 2007, it had an official population of 7,556,900 within the boundaries of Greater London,[20] making it the most populous municipality in the European Union.[21] The Greater London Urban Area (the second largest in the EU) has a population of 8,278,251.[2] while the metropolitan area (the largest in the EU) has an estimated total population of between 12 million[3] and 14 million.[4] The London Underground network, administered by Transport for London, is the most extensive subway network in the world,[22] London Heathrow Airport is the world's busiest airport by number of international passengers[23] and the airspace is the busiest of any urban centre in the world.[24]
London has a temperate marine climate (Koppen climate classification Cfb), like much of the British Isles, so the city rarely sees extremely high or low temperatures. Summers are warm with average high temperatures of 21 °C (70 °F) – 24 °C (75 °F) and lows of 11 °C (52 °F) – 14 °C (57 °F). But temperatures can exceed 25 °C (77 °F) on many days, and in almost every year they exceed 30 °C (86 °F) on some days. The highest temperature ever recorded was 39 °C (102 °F) [87] on 10 August 2003. Winters in London are chilly, but rarely below freezing with daytime highs around 8 °C (46 °F) – 12 °C (54 °F), while spring has mild days and cool evenings.[87] The lowest ever recorded temperature is −21 °C (−5.8 °F) in 1795 and 1796. The lowest in recent years was −10 °C (14.0 °F) on 14 January 1982. Autumn is usually mild but often unsettled as colder air from the north and warmer air from the south meet.
London is a relatively dry city with regular but generally light precipitation throughout the year, with an average of 583.6 millimetres (22.98 in) every year. Snow is relatively uncommon, particularly because heat from the urban area can make London up to 5 °C (9 °F) warmer than the surrounding areas in winter. Some snowfall, however, is usually seen up to a few times a year. The snowfall of February 2009 was the heaviest London had seen for 18 years. London is in USDA Hardiness zone 9, and AHS Heat Zone 2.[88]
Although extreme weather does not happen very often, deep depressions have been known to pass through like the Great Storm of 1987. Tornados are rare, but the Kensal Green area of the city was hit by the 2006 London tornado causing £10 million of damage and injuring 6 people.
In the second half of the 19th century and the first half of the 20th, London was noted for its dense fogs and smogs. Following the deadly Great Smog of 1952, the Clean Air Act 1956 was passed, leading to the decline of such severe pollution in the capital.[89]