|Boroughs of South London|
|Sovereign state||United Kingdom|
|Comprises||Bexley, Bromley, Croydon, Greenwich, Kingston, Lambeth, Lewisham, Merton, Richmond, Southwark, Sutton and Wandsworth|
|o Total||249.34 sq mi (645.78 km2)|
|o Density||11,000/sq mi (4,400/km2)|
In 1720, John Strype's 'Survey of London' described Southwark as one of the then four distinct areas of London; in it he describes the City of London, Westminster (West London), Southwark (South London), and 'That Part beyond the Tower' (East London). The area now usually referred to as North London developed later. As late as the mid 18th century, however, there were no other bridges crossing the river and as a result urban growth was considerably slower in the south than in areas north of the Thames.
The opening of Westminster Bridge and other subsequent bridges to the west encouraged growth in the south-west, but only Tower Bridge was built to the east of London Bridge, so south-east London grew more slowly, at least until the Surrey Commercial Docks were built.
The development of a dense network of railway lines in the mid nineteenth century significantly accelerated growth.
A significant feature of South London's economic geography is that while there are more than thirty bridges linking the area with West London and the City, there is only one, Tower Bridge, linking the area with East London.
Very little of London's underground rail network lies south of the river, largely due to the challenging geology, however 21st century technology makes tunnelling much cheaper than before (though stations are still expensive) and this may well lead to an improved underground provision in South London with the Crossrail 2 line proposed alongside extensions to the Northern and Bakerloo Lines.
South London contains a very extensive overground rail network  and all of London's trams operate within the area.
The 12 boroughs included, in whole or part are:
|London borough||Postcode areas||2008 sub-region||London Assembly|
|Bexley||DA, SE||South East||Bexley and Bromley|
|Bromley||BR, DA, SE, TN, CR||South East||Bexley and Bromley|
|Croydon||CR, SE, SW, BR||South West||Croydon and Sutton|
|Greenwich||SE, DA, BR||South East||Greenwich and Lewisham|
|Kingston||KT, SW, TW||South West||South West|
|Lambeth||SE, SW||South West||Lambeth and Southwark|
|Lewisham||SE, BR||South East||Greenwich and Lewisham|
|Merton||CR, KT, SM, SW||South West||Merton and Wandsworth|
|Richmond (part)||SW, TW||South West||South West|
|Southwark||SE||South East||Lambeth and Southwark|
|Sutton||CR, KT, SM||South West||Croydon and Sutton|
|Wandsworth||SW||South West||Merton and Wandsworth|
The term 'South London' has been used for a variety of formal purposes with the boundaries defined according to the purposes of the designation.
In 2013 the government asked the Boundary Commission for England to reconsider the boundaries of parliamentary constituencies. The Commission's study, was to start with existing regions of England and then group the local authorities within that area into sub-regions for further sub-division. The South London sub-region included all 12 boroughs which lay in whole or part south of the river. The recommendations of the report were not adopted, and the 2017 study has taken a different approach.
For the purposes of progress reporting on the London Plan, there was a South London sub-region in operation from 2004 to 2008 consisting of Bromley, Croydon, Kingston, Merton, Richmond and Sutton. In 2001 this area had a population of 1,329,000. This definition is used by organisations such as Connexions.
Between 2008 and 2011 it was replaced with a South East sub-region consisting of Southwark, Lewisham, Greenwich, Bexley and Bromley and a South West sub-region consisting of Croydon, Kingston, Lambeth, Merton, Sutton, Richmond and Wandsworth.
In 2011 a new South London region was created consisting of Bromley, Croydon, the Royal Borough of Kingston upon Thames, Richmond upon Thames, Merton, Sutton, Wandsworth, Bexley, Greenwich and Lewisham.
South London is, like other parts of London and the UK in general, a temperate maritime climate according to the Köppen climate classification system. Three Met Office weather stations currently collect climate data south of the river; Kew, Hampton and Kenley Airfield, on the southern edge of the urban area. Long term climate observations dating back to 1763 are available for Greenwich, although observations ceased here in 2003.
Temperatures increase towards the Thames, firstly because of the urban warming effect of the surrounding area, but secondly due to altitude decreasing towards the river, meaning the southern margins of South London are often a couple of degrees cooler than those areas adjacent to the Thames. Often snow can be seen to lie on the North Downs near Croydon when central London is snow free.
The record high temperature at Greenwich is 37.5 °C (99.5 °F) recorded during August 2003. Sunshine is notably lower than other London area weather stations (by about 50-100 hours a year), suggesting Greenwich may be a fog trap in winter, and that the hillier land to the south may obscure early morning and late evening sunshine.
The highest temperature recorded across South London was 38.1 °C (100.6 °F) on the same occasion at Kew Gardens. Although the Met Office accepts a higher reading from Brogdale in Kent, many have questioned the accuracy of this and regard the Kew reading as the most reliable highest UK temperature reading.
|Climate data for Greenwich 7m asl 1971-2000,|
|Average high °C (°F)||7.9
|Average low °C (°F)||2.4
|Average precipitation mm (inches)||51.9
|Mean monthly sunshine hours||45.9||66.1||103.2||147.0||185.4||180.6||190.3||194.4||139.2||109.7||60.6||37.8||1,461|