North London is an informally and inexactly defined part of London, England, which covers part of the area of the capital lying north of the River Thames. It extends from Clerkenwell and Finsbury on the edge of the City of London financial district, to Greater London's boundary with Hertfordshire.
The term north London is used to differentiate the area from south London, east London and west London. Some parts of north London are also part of Central London. There is a northern postal area but this includes some areas not normally described as part of north London, while excluding many others that are.
The first northern suburb developed in the Soke of Cripplegate in the early twelfth century, but London's growth beyond its Roman northern gates was slower than in other directions, partly because of the marshy ground north of the wall and also because the roads through those gates were less well connected than elsewhere. The parishes that would become north London were almost entirely rural until the Victorian period. Many of these parishes were grouped into an area called the Finsbury division.
In the early 19th century, the arrival of the Regent's Canal in Islington and St Pancras stimulated London's northerly expansion, continuing when the development of the railway network accelerated urbanisation, promoting economic growth in the capital and allowing for the establishment of commuter suburbs.
This trend continued in the twentieth century and was reinforced by motorcar-based commuting until the establishment of the Metropolitan Green Belt, shortly after the Second World War, prevented London from expanding any further.
The 2011 iteration of the London Plan included an altered 'North' sub-region, to be used for planning, engagement, resource allocation and progress reporting purposes. It consists of the London Boroughs of Barnet, Haringey and Enfield. The 2004-2008 and 2008-2011 versions of the London Plan sub-regions varied in their composition.
In 2017, the government asked the Boundary Commission for England to reconsider the boundaries of parliamentary constituencies. The Commission's approach was to start with existing regions of England (in this case London) and then group the local authorities within that area into sub-regions for further sub-division.
An earlier 2013 study, whose recommendations were not adopted, took a different approach by assigning all of Richmond to the south. This list includes all boroughs included in the North Thames area:
|London borough||Postcode areas||2011 sub-region||London Assembly|
|Barking and Dagenham||IG, RM, E||East||City and East|
|Barnet||EN, HA, N, NW||North||Barnet and Camden|
|Brent||HA, NW, W||West||Brent and Harrow|
|Camden||EC, WC, N, NW||Central||Barnet and Camden|
|Ealing||UB, W, NW||West||Ealing and Hillingdon|
|Enfield||EN, N, E||North||Enfield and Haringey|
|Hackney||E, EC, N||East||North East|
|Hammersmith Fulham||SW, W, NW||West||West Central|
|Haringey||N||North||Enfield and Haringey|
|Harrow||HA, UB, NW||West||Brent and Harrow|
|Havering||RM, CM||East||Havering and Redbridge|
|Hillingdon||HA, TW, UB, WD||West||Ealing and Hillingdon|
|Hounslow||TW, W, UB||West||West|
|Islington||EC, WC, N||Central||North East|
|Kensington and Chelsea||W, SW||Central||West Central|
|Newham||E, IG||East||City and East|
|Redbridge||E, IG, RM||East||Havering and Redbridge|
|Waltham Forest||E, IG||East||North East|
|Westminster||NW, SW, W||Central||West Central|
It has been described as "one of the fiercest derbies in English football and one that separates families in north London." 
The League matches in the English Premier League and formerly the Football League are known formally as the North London Derby. To date, 167 have been contested with 66 wins for Arsenal, 54 wins for Spurs and 47 draws. In other matches, simply referred to generically as North London Derbies, the 6 FA cup contests resulted in 4 Arsenal victories to Spurs' 2 with no draws, while the 14 League Cup matches have ended with 7 wins for the Arsenal against 4 for Spurs with 3 draws. In the sole Charity Shield between the two clubs, then exclusively between the previous season's league champions and the FA Cup winners, the contest in 1991 was drawn with the Shield shared. Spurs won the FA cup final in 1991 after beating Arsenal 3-1 in the semi-final, the first FA cup semi-final and the first of four North London Derbies to be held at Wembley Stadium. The 1991 Charity Shield is the sole occasion so far in which a trophy has been at stake, though in 1971 (0-1) and 2004 (2-2) Arsenal were crowned league champions at the final whistle of the North London Derby in Tottenham.
North London has, like other parts of London and the UK in general, a temperate maritime climate according to the Köppen climate classification system. Long term climate observations dating back to 1910 are available for Hampstead, which also the most elevated Weather Station in the London area, at 137m. This both hilltop and urban position means severe frosts are rare.
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 some of the hillier northern margins of North London are often a degree or so cooler than those areas adjacent to the Thames. Occasionally snow can be seen to lie towards the Chilterns while central London is snow-free.
The average coldest night should fall to -5.6 °C (21.9 °F). On average 35.8 nights will report an air frost, some 119 days of the year will register at least 1mm of precipitation, and on 7.4 days a cover of snow will be observed. All annual averages refer to the observation period 1971-2000.
|Climate data for Hampstead 137m asl 1971-2000|
|Record high °C (°F)||15.7
|Average high °C (°F)||6.8
|Average low °C (°F)||1.6
|Record low °C (°F)||-10.8
|Average precipitation mm (inches)||64.72
|Source: Royal Netherlands Meteorological Institute|