The Northern line is a

London Underground The London Underground (also known simply as the Underground or as the Tube) is a rapid transit system serving Greater London and some parts of the adjacent home counties of Buckinghamshire, Essex and Hertfordshire in England. The Undergro ...

line that runs between

North London North London is the northern part of London, England, north of the River Thames and the City of London. It extends from Clerkenwell and Finsbury, on the edge of the City of London financial district, to Greater London's boundary with Hertfordshi ...

and

South London South London is the southern part of Greater London, England, south of the River Thames. The region consists of the Districts of England, boroughs, in whole or in part, of London Borough of Bexley, Bexley, London Borough of Bromley, Bromley, Lon ...

. It is printed in black on the

Tube map The Tube map (sometimes called the London Underground map) is a schematic transport map of the lines, stations and services of the London Underground, known colloquially as "the Tube", hence the map's name. The first schematic Tube map was des ...

. It carries more passengers per year than any other Underground linearound 340million in 2019making it the busiest tube line in London. The Northern line is unique on the network in having two different routes through Central London, two northern branches and two southern branches. Despite its name, it does not serve the northernmost stations on the Underground, though it does serve the southernmost station at

Morden Morden is a district and town in South London, England, now within the London Borough of Merton, in the ceremonial county of Greater London. It adjoins Merton Park and Wimbledon, London, Wimbledon to the north, Mitcham to the east, Sutton, Londo ...

, the terminus of one of the two southern branches. The line's northern termini, all in the

London Borough of Barnet The London Borough of Barnet () is a suburban London boroughs, London borough in north London, England. Forming part of Outer London, the borough was formed in 1965 from parts of the ceremonial counties of Middlesex and Hertfordshire. It is the ...

, are at and ; is the terminus of a single-station branch line off the High Barnet branch. The two main northern branches run south to join at where two routes, one via in the West End and the other via in the

City A city is a human settlement of a substantial size. The term "city" has different meanings around the world and in some places the settlement can be very small. Even where the term is limited to larger settlements, there is no universally agree ...

, continue and then join at in

Southwark Southwark ( ) is a district of Central London situated on the south bank of the River Thames, forming the north-western part of the wider modern London Borough of Southwark. The district, which is the oldest part of South London, developed ...

. At Kennington the line again divides into two branches, one to each of the southern termini – at , in the borough of Merton, and at in

Wandsworth Wandsworth Town () is a district of south London, within the London Borough of Wandsworth southwest of Charing Cross. The area is identified in the London Plan as one of 35 major centres in Greater London. Toponymy Wandsworth takes its name ...

. For most of its length the Northern line is a deep tube line. The portion between and opened in 1890 and is the oldest section of deep-level tube line on the network. Nearly 340 million passenger journeys were recorded in 2019 on the Northern line, making it the busiest on the Underground, although this is distorted due to having two branches within Central London, both of which are less busy than the core sections of other lines. It has 18 of the system's 31 stations south of the

River Thames The River Thames ( ), known alternatively in parts as the The Isis, River Isis, is a river that flows through southern England including London. At , it is the longest river entirely in England and the Longest rivers of the United Kingdom, s ...

. There are 52 stations in total on the line, of which 38 have platforms below ground. The line's structure of two northern branches (one with a further short branch), two central branches, and two southern branches reflects its complicated history. The core of the line, including the two central branches and the beginnings of the two northern branches, was constructed by two companies, the

City and South London Railway The City and South London Railway (C&SLR) was the first successful deep-level underground "tube" railway in the world, and the first major railway to use Railway electrification in Great Britain, electric traction. The railway was originally i ...

and the

Charing Cross, Euston and Hampstead Railway The Charing Cross, Euston and Hampstead Railway (CCE&HR), also known as the Hampstead Tube, was a railway company established in 1891 that constructed a deep-level underground "tube" railway in London. Construction of the CCE&HR was delayed for ...

, in the 1890s and 1900s. The companies came under the same ownership in 1913, and were physically connected and operationally merged in the 1920s, while at the same time extensions to Edgware and Morden were completed. In the 1930s and 1940s the Northern line took over and electrified the

London and North Eastern Railway The London and North Eastern Railway (LNER) was the second largest (after London, Midland and Scottish Railway, LMS) of the "Big Four (British railway companies), Big Four" railway companies created by the Railways Act 1921 in Britain. It ope ...

branches to Mill Hill East and High Barnet. This was the final extension of the line for eight decades, though between the 1930s and 1970s the

Northern City Line The Northern City Line (NCL) is a commuter railway line in England, which runs from Moorgate station to Finsbury Park in London with services running beyond. It is part of the Great Northern Route services, and operates as the south-eastern b ...

was branded and operated as part of the Northern line despite being disconnected from the rest of the line. The most recent extension, a second southern branch from Kennington to Battersea, opened on 20 September 2021. There are proposals to split the line into two separate lines.

History

Formation

The core of the Northern line evolved from two railway companies: the City & South London Railway (C&SLR) and the Charing Cross, Euston & Hampstead Railway (CCE&HR). The C&SLR was London's first electric hauled deep-level tube railway. It was built under the supervision of

James Henry Greathead James Henry Greathead (6 August 1844 – 21 October 1896) was an English mechanical and civil engineer renowned for his work on the London Underground railways, Winchester Cathedral, and Liverpool overhead railway, as well as being one of the ea ...

, who had been responsible (with

Peter W. Barlow Peter William Barlow (1 February 1809 – 19 May 1885) was an English civil engineer, particularly associated with railways, bridges (he designed the first Lambeth Bridge, a crossing of the River Thames in London), the design of tunnels and th ...

) for the

Tower Subway The Tower Subway is a tunnel beneath the River Thames in central London, between Tower Hill on the north bank of the river and Vine Lane (off Tooley Street) on the south. In 1869 a circular tunnel was dug through the London clay using a cast ir ...

. It was the first of the Underground's lines to be constructed by boring deep below the surface and the first to be operated by electric traction. The railway opened in November 1890 from

Stockwell Stockwell is a district located in South London, part of the London Borough of Lambeth, England. It is situated south of Charing Cross. History The name Stockwell is likely to have originated from a local well, with "stoc" being Old Englis ...

to a now-disused station at King William Street. This was inconveniently placed and unable to cope with the company's traffic so in 1900 a new route to

Moorgate Moorgate was one of the City of London's northern gates in its defensive wall, the last to be built. The gate took its name from the Moorfields, an area of marshy land that lay immediately north of the wall. The gate was demolished in 1762, but ...

via

Bank A bank is a financial institution that accepts Deposit account, deposits from the public and creates a demand deposit while simultaneously making loans. Lending activities can be directly performed by the bank or indirectly through capital m ...

was opened. By 1907, the C&SLR had been further extended at both ends to run from

Clapham Common Clapham Common is a large triangular urban park in Clapham, south London, England. Originally common land for the parishes of Battersea and Clapham, it was converted to parkland under the terms of the Metropolitan Commons Act 1878. It is of gr ...

to Euston. Formation of the Northern Line small

The CCE&HR (commonly known as the "Hampstead Tube") was opened in 1907 and ran from

Charing Cross Charing Cross ( ) is a junction in Westminster, London, England, where six routes meet. Since the early 19th century, Charing Cross has been the notional "centre of London" and became the point from which distances from London are measured. ...

(known for many years as Strand) via Euston and a junction at

Camden Town Camden Town () is an area in the London Borough of Camden, around north-northwest of Charing Cross. Historically in Middlesex, it is identified in the London Plan as one of 34 major centres in Greater London. Laid out as a residential distri ...

Golders Green Golders Green is a suburb in the London Borough of Barnet in north London, northwest of Charing Cross. It began as a medieval small suburban linear settlement near a farm and public grazing area green, and dates to the early 19th century. It ...

and Highgate (now known as Archway). It was extended south by one stop to Embankment in 1914 to form an interchange with the Bakerloo and

District line The District line is a London Underground line running from in the east and Edgware Road tube station (Circle, District and Hammersmith & City lines), Edgware Road in the west to in west London, where it splits into multiple branches. One br ...

s. In 1913, the

Underground Electric Railways Company of London The Underground Electric Railways Company of London, Limited (UERL), known operationally as the Underground for much of its existence, was established in 1902. It was the holding company for the three deep-level "tube"A "tube" railway is an un ...

(UERL), owner of the CCE&HR, took over the C&SLR although they remained separate companies.

Integration

During the early 1920s a series of works were carried out which involved connecting the C&SLR and CCE&HR tunnels to enable an integrated service to be operated. The first of these new tunnels, between the C&SLR's Euston station and the CCE&HR's station at Camden Town, had originally been planned in 1912 but was delayed by the First World War. Construction began in 1922 and this first tunnel opened in 1924. The second connection linking the CCE&HR's Embankment and C&SLR's

Kennington Kennington is a district in south London, England. It is mainly within the London Borough of Lambeth, running along the boundary with the London Borough of Southwark, a boundary which can be discerned from the early medieval period between th ...

stations opened in 1926. It provided a new intermediate station at

Waterloo Waterloo most commonly refers to: * Battle of Waterloo, 1815 battle where Napoleon's French army was defeated by Anglo-allied and Prussian forces * Waterloo, Belgium Waterloo may also refer to: Other places Australia * Waterloo, New South Wale ...

to connect to the main line station there and the

Bakerloo line The Bakerloo line () is a London Underground line that runs between in suburban north-west London and in south London, via the West End. Printed in brown on the Tube map, it serves 25 stations, 15 of which are underground, over . It runs par ...

. The smaller diameter tunnels of the C&SLR were also enlarged to match the standard diameter of the CCE&HR and other deep tube lines.

Extensions

In conjunction with the works to integrate the two lines, two major extensions were undertaken: northwards to

Edgware Edgware () is a suburban town in northwest London. It was an ancient parish in the county of Middlesex east of the ancient Watling Street in what is now the London Borough of Barnet but it is now informally considered to cover a wider area, inc ...

Middlesex Middlesex (; abbreviation: Middx) is a Historic counties of England, former county in South East England, now mainly within Greater London. Its boundaries largely followed three rivers: the River Thames, Thames in the south, the River Lea, Le ...

(now in the

) and southwards to

Surrey Surrey () is a Ceremonial counties of England, ceremonial county in South East England. It is bordered by Greater London to the northeast, Kent to the east, East Sussex, East and West Sussex to the south, and Hampshire and Berkshire to the wes ...

(then in the

Merton and Morden Urban District Merton Urban District (1907–1913) and Merton and Morden Urban District (1913–1965) was an urban district in Surrey, England. It was formed in 1907 from the parish of Merton and was expanded in 1913 to take in Morden. The district was abolishe ...

, but now in the

London Borough of Merton The London Borough of Merton () is a London borough in London, England. The borough was formed under the London Government Act 1963 in 1965 by the merger of the Municipal Borough of Mitcham, the Municipal Borough of Wimbledon and the Merton ...

Edgware Extension

The Edgware extension used plans dating back to 1901 for the Edgware and Hampstead Railway (E&HR) which the UERL's subsidiary, the

London Electric Railway The London Electric Railway (LER) was an underground railway company operating three lines on the London Underground. It was formed in 1910 and existed until 1933, when it was merged into the London Passenger Transport Board. History The LER ...

, had taken over in 1912. It extended the CCE&HR line from its terminus at Golders Green to Edgware in two stages: to Hendon Central in 1923 and to

in 1924. The line crossed open countryside and ran mostly on viaduct from Golders Green to Brent and then on the surface, apart from a short tunnel north of Hendon Central. Five new stations were built to pavilion-style designs by

Stanley Heaps Stanley A. Heaps (1880–1962) was an English architect responsible for the design of a number of stations on the London Underground system as well as the design of train depots and bus and trolleybus garages for London Transport. Works ...

, the UERL's architect, stimulating the rapid northward expansion of suburban developments in the following years.

Morden Extension

The engineering of the Morden extension of the C&SLR from Clapham Common to Morden was more demanding; it runs in tunnels to a point just north of Morden station which was constructed in a cutting. The line then goes under the wide station forecourt and public road outside the station to the depot. The extension was initially planned to continue to

Sutton Sutton (''south settlement'' or ''south town'' in Old English) may refer to: Places United Kingdom England In alphabetical order by county: * Sutton, Bedfordshire * Sutton, Berkshire, a List of United Kingdom locations: Stu-Sz#Su, location * S ...

over part of the route for the unbuilt

Wimbledon and Sutton Railway The Wimbledon and Sutton Railway (W&SR) was a railway company established by an Act of Parliament (UK), Act of Parliament in 1910 to build a railway line in Surrey (now south-west London) from Wimbledon, London, Wimbledon to Sutton, London, Sutt ...

(in which the UERL held a stake) but agreements were made with Southern Railway to end the extension at Morden. Southern Railway built the surface line from Wimbledon to Sutton in the 1930s via South Merton and St. Helier. The tube extension itself opened in 1926 with seven new stations all designed by

Charles Holden Charles Henry Holden (12 May 1875 – 1 May 1960) was an English architect best known for designing many London Underground stations during the 1920s and 1930s, the Underground Electric Railways Company of London's headquarters at 55 Broadwa ...

in a modern style. Originally Stanley Heaps was to design the stations, but after seeing the designs

Frank Pick Frank Pick Royal Institute of British Architects, Hon. RIBA (23 November 1878 – 7 November 1941) was a British transport administrator. After qualifying as a solicitor in 1902, he worked at the North Eastern Railway (UK), North Eastern Ra ...

(Assistant Joint Manager of the UERL) decided that Holden should take over the project. With the exception of Morden and

Clapham South Clapham South () is a London Underground station. It is on the Northern line between and Balham stations, and is in both Travelcard Zone 2 and Travelcard Zone 3. The station is located at the corner of Balham Hill (A24) and Nightingale Lane, ...

, where more land was available, the new stations were built on confined corner sites at main road junctions in areas that had been already developed. Holden made good use of this limited space and designed striking buildings. The street-level structures are of white

Portland stone Portland stone is a limestone geological formation (formally named the Portland Stone Formation) dating to the Tithonian age of the Late Jurassic that is quarried on the Isle of Portland in Dorset, England. The quarries are cut in beds of whi ...

with tall double-height ticket halls, with the London Underground roundel made up in coloured glass panels in large glazed screens. The stone columns framing the glass screens are surmounted by a capital formed as a three-dimensional version of the roundel. The large expanses of glass above the entrances ensure that the ticket halls are bright and lit from within at night, creating a welcoming feel. The first and last new stations on the extension, Clapham South and Morden, include a parade of shops and were designed with structures capable of being built above (like many of the earlier

central London Central London is the innermost part of London, in England, spanning the City of London and several boroughs. Over time, a number of definitions have been used to define the scope of Central London for statistics, urban planning and local gove ...

stations). Clapham South was extended upwards soon after its construction with a block of apartments; Morden was extended upwards in the 1960s with a block of offices. All the stations on the extension, except Morden itself, are Grade II

listed building In the United Kingdom, a listed building is a structure of particular architectural or historic interest deserving of special protection. Such buildings are placed on one of the four statutory lists maintained by Historic England in England, Hi ...

Great Northern & City Railway

After the UERL and the

Metropolitan Railway The Metropolitan Railway (also known as the Met) was a passenger and goods railway that served London from 1863 to 1933, its main line heading north-west from the capital's financial heart in the City to what were to become the Middlesex su ...

became part of the new unified

London Passenger Transport Board The London Passenger Transport Board was the organisation responsible for local public transport in London and its environs from 1933 to 1948. In common with all London transport authorities from 1933 to 2000, the public name and brand was Londo ...

in 1933, the MR's subsidiary the

Great Northern & City Railway The Northern City Line (NCL) is a commuter railway line in England, which runs from Moorgate station to Finsbury Park in London with services running beyond. It is part of the Great Northern Route services, and operates as the south-eastern b ...

became part of the Underground as the Northern City Line. It ran underground from Moorgate to

Finsbury Park Finsbury Park is a public park in Harringay, north London, England. The park lies on the southern-most edge of the London Borough of Haringey. It is in the area formerly covered by the historic parish of Hornsey, succeeded by the Municipal ...

. In preparation for the Northern Heights Plan it was operated as part of the Northern line, although it was never connected to the rest of the line.

Naming

The resulting line became known as the Morden–Edgware line, although a number of alternative names were also mooted in the fashion of the contraction of Baker Street & Waterloo Railway to "Bakerloo", such as "Edgmor", "Mordenware", "Medgeway" and "Edgmorden". It was eventually named the ''Northern line'' from 28 August 1937, reflecting the planned addition of the Northern Heights lines.

Northern Heights plan

Northern Line Northern Heights Extension sign

In June 1935 the LPTB announced the

New Works Programme The New Works Programme of 1935–1940 was the major investment programme delivered by the London Passenger Transport Board (LPTB), commonly known as London Transport, which had been created in 1933 to coordinate underground train, tram, trolle ...

, an ambitious plan to expand the Underground network which included the integration of a complex of existing

(LNER) lines north of

Highgate Highgate is a suburban area of N postcode area, north London in the London Borough of Camden, London Boroughs of Camden, London Borough of Islington, Islington and London Borough of Haringey, Haringey. The area is at the north-eastern corner ...

through the Northern Heights. These lines, built in the 1860s and 1870s by the

Edgware, Highgate and London Railway The Edgware, Highgate and London Railway was a railway in North London, England. The railway was a precursor of parts of London Underground's Northern line and was, in the 1930s, the core of an ambitious expansion plan for that line which was t ...

(EH&LR) and its successors, ran from Finsbury Park to

via Highgate, with branches to

Alexandra Palace Alexandra Palace is an entertainment and sports venue in North London, situated between Wood Green and Muswell Hill in the London Borough of Haringey. A listed building, Grade II listed building, it is built on the site of Tottenham Wood and th ...

and

High Barnet Chipping Barnet or High Barnet is a suburban market town in north London, forming part of the London Borough of Barnet, England. It is a suburban development built around a 12th-century settlement, and is located north-northwest of Charing C ...

. The line taken over would be extended beyond Edgware to

Brockley Hill Brockley Hill, Stanmore, is an area of high ground on the outskirts of North London, England. The hill, which rises to above sea level, is traversed by the A5 road. It follows the course of the Roman road known as Watling Street. The hill is a ...

, Elstree South and

Bushey Heath Bushey is a town in the Hertsmere borough of Hertfordshire in the East of England. It had a population of 25,328 in the 2011 census, rising to 28,416 in the 2021 census, an increase of 12.19%. This makes Bushey the second most populated town ...

with a new depot at

Aldenham Aldenham is a village and Civil parishes in England, civil parish in the borough of Hertsmere in Hertfordshire, England. The parish includes Radlett and Letchmore Heath as well as Aldenham village itself. The village of Aldenham lies north-eas ...

. The extension's route was that planned for the unbuilt Watford and Edgware Railway (W&ER), using rights obtained from the earlier purchase of the W&ER (which had long intended an extension of the EH&LR Edgware route towards

Watford Watford () is a town and non-metropolitan district with Borough status in the United Kingdom, borough status in Hertfordshire, England, northwest of Central London, on the banks of the River Colne, Hertfordshire, River Colne. Initially a smal ...

). This also provided the potential for further extension in the future;

Bushey Bushey is a town in the Hertsmere borough of Hertfordshire in the East of England. It had a population of 25,328 in the 2011 census, rising to 28,416 in the 2021 census, an increase of 12.19%. This makes Bushey the second most populated town ...

's town planners reserved space in Bushey village for a future station and Bushey Heath station's design was revised several times to ensure this option would remain available in the future. The project involved

electrification Electrification is the process of powering by electricity and, in many contexts, the introduction of such power by changing over from an earlier power source. In the context of history of technology and economic development, electrification refe ...

of the surface lines (operated by steam trains at the time), the doubling of the original single-line section between Finchley Central and the proposed junction with the Edgware branch of the Northern line, and the construction of three new linking sections of track: a connection between Northern City Line and Finsbury Park station on the surface; an extension from Archway to the LNER line near

East Finchley East Finchley is an area in North London, immediately north of Hampstead Heath. Like neighbouring Muswell Hill, it straddles the London Boroughs of London Borough of Barnet, Barnet and London Borough of Haringey, Haringey, with most of East F ...

via new deep-level platforms below Highgate station; and a short diversion from just before the LNER's Edgware station to the Underground's station of the same name.

Intended service levels

The peak-hour service pattern was to be 21 trains an hour each way on the High Barnet branch north of Camden Town, 14 of them via the Charing Cross branch and seven via the Bank branch. 14 would have continued on beyond Finchley Central, seven each on the High Barnet and Edgware branches. An additional seven trains an hour would have served the High Barnet branch but continued via Highgate High-Level and Finsbury Park to Moorgate, a slightly shorter route to the city. It does not seem to have been intended to run through trains to the ex-Northern City branch from Edgware via Finchley Central. Seven trains an hour would have served the Alexandra Palace branch, to/from Moorgate via Highgate High-Level. In addition to the 14 through trains described the ex-Northern City branch would have had 14 four-car shuttle trains an hour.

Progress of works

Work began in the late 1930s and was in progress on all fronts by the outbreak of the

Second World War World War II or the Second World War (1 September 1939 – 2 September 1945) was a World war, global conflict between two coalitions: the Allies of World War II, Allies and the Axis powers. World War II by country, Nearly all of the wo ...

. The tunnelling northwards from the original Highgate station (now Archway) had been completed, and the service to the rebuilt surface station at

started on 3 July 1939 but without the opening of the intermediate (new) Highgate Station at the site of the LNER's station of the same name. Further progress was disrupted by the start of the war; however enough development had been made to complete the electrification of the

branch onwards from East Finchley (over which tube services started on 14 April 1940) and the new deep-level

station opened on 19 January 1941. The single track LNER line to Edgware was electrified as far as Mill Hill East, including the

Dollis Brook Viaduct The Dollis Brook Viaduct, also known as the Dollis Road Viaduct, Dollis Viaduct or Mill Hill Viaduct, is a railway viaduct to the west of Finchley, North London, United Kingdom. It carries the London Underground's Northern line from Mill Hill Ea ...

, opening as a tube service on 18 May 1941 to serve the barracks there thus forming the Northern line as it is today. The new depot at Aldenham had already been built and was used to build Halifax bombers. Work on the other elements of the plan was suspended late in 1939. Work on the extension from Edgware to Bushey Heath including work on a viaduct and a tunnel started in June 1939, but was stopped after war broke out. After the war, the area beyond Edgware was made part of the

Metropolitan Green Belt The Metropolitan Green Belt is a statutory green belt around London, England. It comprises parts of Greater London, Berkshire, Buckinghamshire, Essex, Hertfordshire, Kent and Surrey, parts of two of the three districts of Bedfordshire and a s ...

, largely preventing the anticipated residential development in the area, and the potential demand for services from Bushey Heath thus vanished. Passenger numbers also dropped on the then- BR's Mill Hill and Alexandra Palace branches, so it was useless to electrify them. Available funds were directed towards completing the eastern extension of the Central line instead, and the Northern Heights plan was dropped on 9 February 1954. Aldenham depot was converted into an overhaul facility for buses. The implemented service from High Barnet branch gave good access both to the West End and the

. This appears to have undermined traffic on the Alexandra Palace branch, still run with steam haulage to Kings Cross via Finsbury Park, as Highgate (low-level) was but a short bus ride away and car traffic was much lighter than it would become later. Consequently, the line from Finsbury Park to Muswell Hill and Alexandra Palace via the surface platforms at Highgate was closed altogether to passenger traffic in 1954. This contrasts with the decision to electrify the Epping-Ongar branch of the Central line, another remnant of the New Works programme, run as a tube-train shuttle from 1957. A local pressure group, the Muswell Hill Metro Group, campaigns to reopen this route as a light-rail service. So far there is no sign of movement on this issue: the route, now the

Parkland Walk The Parkland Walk is a linear green pedestrian and cycle route in London, which follows the course of the railway line that used to run between Finsbury Park and Alexandra Palace, through Stroud Green, London, Stroud Green, Crouch End, High ...

, is highly valued by walkers and cyclists, and suggestions in the 1990s that it could, in part, become a road were met with fierce opposition. Another pressure group has proposed using the track bed further north, as part of the North and West London Light Railway. The connection between Drayton Park and the surface platforms at Finsbury Park was opened in 1976, when the Northern City Line became part of

British Rail British Railways (BR), which from 1965 traded as British Rail, was a state-owned company that operated most rail transport in Great Britain from 1948 to 1997. Originally a trading brand of the Railway Executive of the British Transport Comm ...

1990s refurbishment and upgrade

In the 1980s, a southern extension of the line to

Peckham Peckham ( ) is a district in south-east London, within the London Borough of Southwark. It is south-east of Charing Cross. At the 2001 Census the Peckham ward had a population of 14,720. History "Peckham" is a Saxon place name meaning the vi ...

was proposed, as part of a review of potential extensions of Underground lines. The proposal was not proceeded with. By the early 1990s, the line had deteriorated due to years of under-investment and the use of old

rolling stock The term rolling stock in the rail transport industry refers to railway vehicles, including both powered and unpowered vehicles: for example, locomotives, Railroad car#Freight cars, freight and Passenger railroad car, passenger cars (or coaches) ...

, most of which dated back to the early 1960s. The line gained the nickname "Misery Line" due to its perceived unreliability. In 1995, a comprehensive refurbishment of the line began – including track replacement, power upgrades, station modernisation (such as

Mornington Crescent Mornington Crescent is a terraced street in Camden Town, London Borough of Camden, Camden, London, England. It was built in the 1820s, on a greenfield site just to the north of central London. Many of the houses were subdivided into flats dur ...

) and the replacement of older rolling stock with new 1995 Stock thanks to a

public–private partnership A public–private partnership (PPP, 3P, or P3) is a long-term arrangement between a government and private sectors, private sector institutions.Hodge, G. A and Greve, C. (2007), Public–Private Partnerships: An International Performance Revie ...

deal with

Alstom Alstom SA () is a French multinational rolling stock manufacturer which operates worldwide in rail transport markets. It is active in the fields of passenger transportation, signaling, and locomotives, producing high-speed, suburban, regional ...

Recent developments

Throughout the 2000s, no plans were considered for extending the Northern line, as the PPP to upgrade the Underground did not include provision for line extensions within the PPP contracts. The Northern line was originally scheduled to switch to

automatic train operation Automatic train operation (ATO) is a method of operating trains automatically where the driver is not required or is required for supervision at most. Alternatively, ATO can be defined as a subsystem within the automatic train control, which pe ...

in 2012, using the same

SelTrac SelTrac is a digital railway signalling technology used to automatically control the movements of rail vehicles. It was the first fully automatic moving-block signalling system to be commercially implemented. SelTrac was originally developed ...

S40 system as used since 2009 on the

Jubilee line The Jubilee line is a London Underground line that runs between in suburban north-west London and in east London, via the West End of London, West End, South Bank and London Docklands, Docklands. Opened in 1979, it is the newest line on the ...

and for a number of years on the

Docklands Light Railway The Docklands Light Railway (DLR) is an automated medium-capacity rail system, light metro system primarily serving the redeveloped London Docklands, Docklands area of London and providing a direct connection between London's two major financi ...

. Originally the work was to follow on from the Jubilee line so as to benefit from the experience of installing it there, but that project was not completed until spring 2011. Work on the Northern line was contracted to be completed before the

2012 Olympics The 2012 Summer Olympics, officially the Games of the XXX Olympiad and also known as London 2012, were an international multi-sport event held from 27 July to 12 August 2012 in London, England, United Kingdom. The first event, the ...

. It was then undertaken in-house, and TfL predicted the upgrade would be complete by the end of 2014. The first section of the line (West Finchley to High Barnet) was transferred to the new signalling system on 26 February 2013 and the line became fully automated on 1 June 2014, with the Chalk Farm to Edgware via Golders Green section being the last part of the line to switch to ATO. In January 2018, Transport for London announced that it would double the period during which it runs peak evening services in the central London section to tackle overcrowding. There would now be 24 trains per hour on both central London branches and the northern branches, as well as 30 trains per hour on the Kennington to Morden section between 5pm and 7pm.

24-hour weekend service

Since the mid-autumn of 2016, a 24-hour "

Night Tube The Night Tube and London Overground Night Service, often referred to simply as Night Tube, is a service pattern on the London Underground ("Tube") and London Overground systems which provides through-the-night services on Friday and Saturday ni ...

" service has run on Friday and Saturday nights from Edgware and High Barnet to Morden via the Charing Cross branch; service is suspended on the Bank branch during these times. Trains run every eight minutes between Morden and Camden Town and every 15/16 minutes between Camden Town and Edgware/High Barnet. Labour disputes delayed the planned start date of September 2015.

Battersea extension

In September 2021, the Northern line was extended to serve the redevelopment of

Battersea Power Station Battersea Power Station is a decommissioned coal-fired power station located on the south bank of the River Thames in Nine Elms, Battersea in the London Borough of Wandsworth. It was built by the London Power Company (LPC) to the design of ...

. Partially funded by private developers, the £1.2bn project extended the Charing Cross branch of the line for from

to Battersea Power Station, with an intermediate stop at Nine Elms. Approved by Wandsworth Council in 2010 and TfL in 2014, the construction of the line began in 2015. Tunnelling for the project was completed in 2017, and the extension opened on 20 September 2021. Provision has been made for a future extension to

Clapham Junction railway station Clapham Junction () is a major railway station near St John's Hill in south-west Battersea, in the London Borough of Wandsworth, England. It lies from and from . Despite its name, Clapham Junction is not in Clapham, a district to the south- ...

Services

Peak

As of September 2021, morning peak southbound services are: *4 from Edgware to Battersea Power Station via Charing Cross *2 tph from Edgware to Morden via Charing Cross *12 tph from Edgware to Morden via Bank *10 tph from High Barnet to Battersea Power Station via Charing Cross *2 tph from High Barnet to Morden via Charing Cross *8 tph from High Barnet to Morden via Bank *2 tph from Mill Hill East to Battersea Power Station via Charing Cross *2 tph from Mill Hill East to Morden via Bank This service pattern provides 20 tph between Finchley Central and High Barnet, 4 tph between Finchley Central and Mill Hill East, 16 tph between Kennington and Battersea Power Station and 22 tph everywhere else on the line except between Kennington and Morden, between Camden Town and Finchley Central and on the Edgware branch where there will be 24 tph.

Off-peak

As of November 2022, off-peak services are the similar to peak services, minus the four hourly trains that run from Morden to the northern branches via Charing Cross: *10 tph from Edgware to Battersea Power Station via Charing Cross *10 tph from Edgware to Morden via Bank *8 tph from High Barnet to Battersea Power Station via Charing Cross *8 tph from High Barnet to Morden via Bank *2 tph from Mill Hill East to Battersea Power Station via Charing Cross *2 tph from Mill Hill East to Morden via Bank This service pattern provides 16 tph between Finchley Central and High Barnet, 4 tph between Finchley Central and Mill Hill East, and 20 tph everywhere else on the line.

Night

Since 2016, the Northern line has operated

services on Friday and Saturday nights between the Edgware and High Barnet termini and Morden, via the Charing Cross branch only. Trains run every 15 minutes on each of the northern branches, combining to give eight trains per hour between Camden Town and Morden. There is no Night Tube service on the Mill Hill East, Bank, or Battersea branches. *4 tph from High Barnet to Morden via Charing Cross *4 tph from Edgware to Morden via Charing Cross

Map

Stations

Open stations

High Barnet branch

Edgware branch

Camden Town

Charing Cross branch

Bank branch

Kennington

Battersea branch

Morden branch

Closed stations

Permanently closed stations

* King William Street (closed 1900; replaced by

) *

City Road City Road or The City Road is a road that runs through central London. The northwestern extremity of the road is at Angel where it forms a continuation of Pentonville Road. Pentonville Road itself is the modern name for the eastern part of Lo ...

(closed 1922) * South Kentish Town (closed 1924) * North End (also known as "Bull & Bush". Never opened; work stopped 1906)

Resited stations

– new platforms resited immediately to the south of its predecessor with the 1922–1924 upgrade of the line. *

London Bridge The name "London Bridge" refers to several historic crossings that have spanned the River Thames between the City of London and Southwark in central London since Roman Britain, Roman times. The current crossing, which opened to traffic in 197 ...

– the northbound tunnel and platform converted into a concourse, and a new northbound tunnel and platform built in the late 1990s to increase the platform and circulation areas in preparation for the opening of the Jubilee line.

Abandoned plans

=Northern Heights stations not transferred from LNER

= *

– High-level only *

Stroud Green Stroud Green is a suburb and Ward (subnational entity), electoral ward in north London, England, split between the London boroughs of London Borough of Haringey, Haringey and London Borough of Islington, Islington. On its south-western side, St ...

Crouch End Crouch End is an area of North London, England, from the City of London in the western half of the borough of Haringey. It is within the Hornsey postal district (N8). It has been described as one of "a new breed of urban villages" in London ...

* Cranley Gardens *

Muswell Hill Muswell Hill is a suburban district of the London Borough of Haringey, north London. The hill, which reaches over above sea level, is situated north of Charing Cross. Neighbouring areas include Highgate, London, Highgate, Hampstead Garden ...

* Mill Hill (The Hale)

=Bushey Extension stations not constructed

= *

* Elstree South *

Infrastructure

Rolling stock

When the line opened, it was served by 1906 Stock. This was replaced by Standard stock which was in turn replaced by

1938 stock The London Underground 1938 Stock is a London Underground tube stock design. A total of 1,121 cars were built by Metro-Cammell and Birmingham RC&W. An additional 173 cars were added to the fleet by the end of 1953, comprising 91 new bui ...

as part of the New Works Programme, later supplemented with identical 1949 Stock. When the

Piccadilly line The Piccadilly line is a Deep level underground, deep-level London Underground line running between the west and the north of London. It has two western branches which split at Acton Town tube station, Acton Town and serves 53 stations. The li ...

was extended to

Heathrow Airport Heathrow Airport , also colloquially known as London Heathrow Airport and named ''London Airport'' until 1966, is the primary and largest international airport serving London, the capital and most populous city of England and the United Kingdo ...

in the 1970s, its 1959 Stock and 1956 Stock (prototypes of the 1959 Stock) trains were transferred to the Northern line. As there were not enough 1956 and 1959 Stock trains to replace the Northern line's 1938 Stock fleet, they were supplemented with newly built 1972 Mark 1 Stock trains, which all served the line at the same time. 1972 Mark 2 stock trains also ran on this line until going to the

; they were then moved to the

, where they remain in service. By 1986, increasing unreliability of 1959 stock trains meant there were regularly too few trains to run a full peak service. Five 1938 stock trains, newly retired from the Bakerloo Line, were overhauled and returned to the Northern Line to serve another two years until further 1972 stock could be transferred from the Jubilee Line, which was moving to 1983 stock. The few 1956 Stock trains were briefly replaced by 1962 Stock transferred from the Central line in 1995, before the entire Northern line fleet was replaced with 1995 Stock between 1998 and 2000. Today, all Northern line trains consist of 1995 Stock in the Underground livery of red, white and blue. In common with the other deep-level lines, the trains are the smaller of the two

loading gauge A loading gauge is a diagram or physical structure that defines the maximum height and width dimensions in railway vehicles and their loads. Their purpose is to ensure that rail vehicles can pass safely through tunnels and under bridges, and k ...

s used on the system. 1995 stock has automated announcements and quick-close doors. If the proposed split of the line takes place (initial estimates of 2018 having been abandoned to focus on completion of the Battersea and Nine Elms extension work), 19 new trains will be added to the existing fleet of 106 trains, though additional trains beyond the extra 19 trains may be required to provide a full service for the new Battersea extension.

Tunnels

Although two other London Underground lines operate fully underground, the Northern line is unusual in that it is a deep-level tube line that serves the outer suburbs of South London yet there is only one station above ground (Morden tube station) while the rest of this part of the line is deep below ground. The short section to Morden depot is also above ground. This is partly because its southern extension into the outer suburbs was not done by taking over an existing surface line as was generally the case with routes such as the Central,

Jubilee A jubilee is often used to refer to the celebration of a particular anniversary of an event, usually denoting the 25th, 40th, 50th, 60th, and the 70th anniversary. The term comes from the Hebrew Bible (see, "Old Testament"), initially concerning ...

and

s. Apart from the core central underground tunnels, part of the section between

Hendon Hendon is an urban area in the London Borough of Barnet, northwest London northwest of Charing Cross. Hendon was an ancient Manorialism, manor and parish in the county of Middlesex and a former borough, the Municipal Borough of Hendon; it has ...

and

Colindale Colindale is a district in the London Borough of Barnet; its main shopping street on the A5 forming the borough boundary with neighbouring Brent. Colindale is a suburban area, and in recent years has had many new apartments built. It is also ...

is also underground. As bicycles are not allowed in tunnel sections (even if no station is in that section) as they would hinder evacuation, they are limited to High Barnet – East Finchley, the Mill Hill East branch, Edgware – Colindale and Hendon Central – Golders Green. There are also time-based restrictions for the sections where bicycles are allowed. The tunnel from Morden to East Finchley via Bank, 17 miles 528 yards (27.841 km), was for a time the longest rail tunnel in the world. Other tunnels, including the

Channel Tunnel The Channel Tunnel (), sometimes referred to by the Portmanteau, portmanteau Chunnel, is a undersea railway tunnel, opened in 1994, that connects Folkestone (Kent, England) with Coquelles (Pas-de-Calais, France) beneath the English Channel at ...

that links the UK and France, are now longer.

Depots

The Northern line is serviced by four depots. The main one is at

, adjacent to Golders Green tube station, while the second, at

, is south of Morden tube station and is the larger of the two. The other two are at Edgware and Highgate. The Highgate depot is on the former LNER branch to Alexandra Palace. There was originally a depot at Stockwell, but this closed in 1915. There are sidings at High Barnet for stabling trains overnight.

Future

Northern line split

Since the 2000s, TfL has aspired to split the Northern line into two separate routes. Running trains between all combinations of branches and the two central sections, as at present, means only 24 trains an hour can run through each of the central sections at peak times, because merging trains have to wait for each other at the junctions at

and

. Completely segregating the routes could allow 36 trains an hour on all parts of the line, increasing capacity by around 25%. TfL has already separated the Charing Cross and Bank branches during off-peak periods; however, four trains per hour still run to and from Morden via Charing Cross in the peak; the northern branches to Edgware and High Barnet cannot be separated until Camden Town station is upgraded to cope with the numbers of passengers changing trains. The extension to Battersea would allow the

branch to terminate at Battersea Power Station. The proposed split of the Northern line would require Camden Town station to be expanded and upgraded, as the station is already severely overcrowded at weekend peak times, and a split would increase the number of passengers wishing to change trains at the station. Detailed report, with updated timeline etc. In 2005, London Underground failed to secure planning permission for a comprehensive upgrade plan for Camden Town tube station that would have involved demolition of the existing station entrance and several other surface-level buildings, all within a

conservation area Protected areas or conservation areas are locations which receive protection because of their recognized natural or cultural values. Protected areas are those areas in which human presence or the exploitation of natural resources (e.g. firewoo ...

. New redevelopment plans were first announced in 2013 by TfL, which proposed avoiding the existing station entrance and the conservation area by building a second entrance and interchange tunnels to the north, mostly on the site of a subsequently vacated

infant school An infant school is a type of school or school department for young children. Today, the term is mainly used in England and Wales. In the Republic of Ireland, the first two years of primary school are called infant classes. Infant schools were ...

. In 2018, plans to upgrade and rebuild Camden Town station were placed indefinitely on hold, due to TfL's financial situation. , TfL said they still "aspire" to split the line. A partial separation was proposed in which all trains from Morden would operate via Bank, while those starting at Kennington (or Battersea) would serve the Charing Cross branch. The High Barnet and Edgware branches would remain served by trains from both routes.

Incidents and accidents

In October 2003, a train derailed at

. Although no one was hurt, points, signals and carriages were damaged. Concern was raised about the safety of the Tube, given the derailment at

Chancery Lane Chancery Lane is a one-way street that forms part of the City of London#Boundary, western boundary of the City of London. The east side of the street is entirely within the City,Tube Lines Tube Lines Limited, initially known as ''Infraco JNP'' (an amalgamation of infrastructure and company), was an asset-management company responsible for the maintenance, renewal and upgrade of the infrastructure, including track, trains, signals ...

concluded that poor

track geometry Track geometry is concerned with the properties and relations of points, lines, curves, and surfaces in the three-dimensional positioning of railroad Track (rail transport), track. The term is also applied to measurements used in design, construct ...

was the main cause, and therefore extra friction arising out of striations (scratches) on a newly installed set of points had allowed the leading wheel of the last carriage to climb the rail and derail. The track geometry at the derailment site is a very tight bend and tight tunnel bore, which precludes the normal solution for this sort of geometry of canting the track by raising the height of one rail relative to the other. In August 2010, a defective

rail grinding High-speed grinding (HSG) is a rail care concept developed by the company Stahlberg Roensch from Seevetal, Germany. It is based on the principle of rotational grinding and serves to grind rails at up to . Background Since roughly the beginn ...

train caused disruption on the Charing Cross branch, after it travelled four miles in 13 minutes without a driver. The train was being towed to the depot after becoming faulty. At Archway station, the defective train became detached and ran driverless until coming to a stop at an incline near Warren Street station. This caused morning rush-hour services to be suspended on this branch. All passenger trains were diverted via the Bank branch, with several not stopping at stations until they were safely on the Bank branch.

In popular culture

* In his

debut novel A debut novel is the first novel a novelist publishes. Debut novels are often the author's first opportunity to make an impact on the publishing industry, and thus the success or failure of a debut novel can affect the ability of the author to pu ...

'' Ghostwritten'', David Mitchell characterises the Northern line as "the psycho of the family". * The

Bloc Party Bloc Party are an English Rock music, rock band that was formed in London, England, London in 1999 by co-founders Kele Okereke (lead vocals, rhythm guitar, piano, sampler) and Russell Lissack (lead guitar). Their first four albums all featur ...

song "Waiting For the 7.18" references the Northern line as "the loudest". * As part of a series of twelve books tied to the twelve lines of the London Underground, A ''Northern Line Minute'' focuses on the Northern line. * The New Vaudeville Band's 1967 song "Finchley Central" ("On Tour" in the US) mentions several stations on the line. * The

Nick Drake Nicholas Rodney Drake (19 June 1948 – 25 November 1974) was an English singer-songwriter and musician. An accomplished acoustic guitarist, Drake signed to Island Records at the age of twenty while still a student at the University of Cambridg ...

song "Parasite" references the Northern Line. * The 1982

Robyn Hitchcock Robyn Rowan Hitchcock (born 3 March 1953) is an English singer-songwriter and guitarist. While primarily a vocalist and guitarist, he also plays harmonica, piano, and bass guitar. After leading the Soft Boys in the late 1970s and releasing the ...

song "Fifty Two Stations" begins, "There's fifty-two stations on the Northern Line/None of them is yours, one of them is mine." * The 2021

Maisie Peters Maisie Hannah Peters (born 28 May 2000) is an English singer-songwriter. She began her professional career independently, releasing two singles, "Place We Were Made" and "Birthday". In 2018, she signed with Atlantic Records, releasing two EPs a ...

song "Elvis Song" begins, "Cold bench on a platform/Last train on the Northern Line."

Maps

*High Barnet – *Totteridge & Whetstone – *Woodside Park – *West Finchley – *Mill Hill East – *Finchley Central – *East Finchley – *Highgate – *Archway – *Tufnell Park – *Kentish Town – *Edgware – *Burnt Oak – *Colindale – *Hendon Central – *Brent Cross – *Golders Green – *Hampstead – *Belsize Park – *Chalk Farm – *Camden Town – *Mornington Crescent – *Euston – *Warren Street – *Goodge Street – *Tottenham Court Road – *Leicester Square – *Charing Cross – *Embankment – *Waterloo – *King's Cross St Pancras – *Angel – *Old Street – *Moorgate – *Bank-Monument – *London Bridge – *Borough – *Elephant & Castle – *Kennington – *Oval – *Stockwell – *Clapham North – *Clapham Common – *Clapham South – *Balham – *Tooting Bec – *Tooting Broadway – *Colliers Wood – *South Wimbledon – *Morden – *Golders Green depot – *Morden depot –

Explanatory footnotes

References

Notes

Citations

Bibliography

* * * * * * * * * * * * * * *

External links

Above-ground route of line from Morden to Edgware
constructed from Google StreetView
Architectural history of London Underground during 1920-30s
from the

Royal Institute of British Architects The Royal Institute of British Architects (RIBA) is a professional body for architects primarily in the United Kingdom, but also internationally, founded for the advancement of architecture under its royal charter granted in 1837, three suppl ...