This line is one of two Underground lines that cross the Greater London boundary and proceed outwards into theHome Counties, the other being theCentral line. It is the only Underground line with an express service at peak times; the longer distance between stations means trains can achieve the system's highest speeds, up to 62 miles per hour (100 km/h), on some sections.
In 1863, theMetropolitan Railway was the world's first underground railway. It first ran betweenPaddington andFarringdon, with wooden carriages and steam locomotives, subsequently extending north-westwards into theMiddlesex countryside, where it stimulated the development of new suburbs. Harrow was reached in 1880, and ultimately the line continued as far asVerney Junction, in Buckinghamshire, more than 50 miles (80 km) fromBaker Street. From the end of the 19th century, the railway shared tracks with theGreat Central Railway out ofMarylebone. The central London lines were electrified by 1907, but electric locomotives were exchanged for steam locomotives on trains heading north of Harrow. After the railway was absorbed by theLondon Passenger Transport Board in 1933, the line was cut back toAylesbury. Steam trains ran until 1961, when the line was electrified to, and services were curtailed at, Amersham. TheHammersmith & City line was shown on the tube map as a part of the Metropolitan line until 1990, when it appeared as a separate line. The currentS8 Stock trains entered service between 2010 and 2012, replacing theA Stock trains, which had served since 1961.
The section between Aldgate and Baker Street is shared with theCircle line; between Liverpool Street and Baker Street with theHammersmith & City line; betweenRayners Lane and Uxbridge with thePiccadilly line; and betweenHarrow-on-the-Hill and Amersham with theLondon–Aylesbury line operated byChiltern Railways. Baker Street is the southbound terminus for some trains not continuing to Aldgate. Most of the route has two tracks, except for the single-trackChesham branch and a four-track section betweenWembley Park andMoor Park, which allows fast and semi-fast services to overtake "all stations" trains. There are four tracks between Wembley Park and Finchley Road: only the outer ones are used by the Metropolitan line's non-stop trains; the inner pair was transferred to theBakerloo line in 1939 (and became theJubilee line in 1979) with services calling at all stations.
Construction of the Metropolitan line near King's Cross station (1861)
The Metropolitan Railway, also known asthe Met, was a passenger and goods railway that served London from 1863 to 1933, its main line heading north-west fromthe City to what were to become theMiddlesex suburbs. Its first line connected the mainline railway termini atPaddington,Euston andKing's Cross to the City, built beneath theNew Road using thecut-and-cover method between Paddington and King's Cross, and in tunnel and cuttings besideFarringdon Road from King's Cross to nearSmithfield. The world's first underground railway, it opened on 10 January 1863 with gas-lit wooden carriages hauled by steam locomotives. The line operated at a frequency of three trains per hour, rising to four trains per hour during the peak periods.[5][6][7] In the 1871 plans for an underground railway in Paris, it was called theMétropolitain.[8]
The railway was soon extended from both ends and northwards via a branch fromBaker Street. It reachedHammersmith in 1864 andRichmond in 1877; it completed theInner Circle in 1884,[9] but the most important route became the line west and north-west into the Middlesex countryside, where it stimulated the development of new suburbs.Harrow was reached in 1880, and ultimately, as far asVerney Junction inBuckinghamshire, more than 50 miles (80 kilometres) from Baker Street. From the end of the 19th century, the railway shared tracks with theGreat Central Railway route out ofMarylebone.[10]
12Sarah Siddons with vintage train at Hammersmith
Electric traction was introduced in 1905 withelectric multiple units operating between Uxbridge, Harrow-on-the-Hill and Baker Street. To remove steam and smoke from the tunnels in central London, the railway purchasedelectric locomotives, exchanged for steam locomotives at Harrow from 1908.[11] In 1910, a seventeen-minute silent film was made showing large portions of the journey from Baker Street to Aylesbury and Uxbridge, seen from the cab of a train.[12]
To improve services, more powerful electric and steam locomotives were purchased in the 1920s. A short branch opened from Rickmansworth to Watford in 1925. AfterWorld War I, the 4-mile (6.4 km) Stanmore branch was built from Wembley Park.[13]
On 1 July 1933, the Metropolitan was amalgamated with other Underground railways, tramway companies and bus operators to form theLondon Passenger Transport Board, and a period of rationalisation followed.
While the Metropolitan was run as an outer suburban route with steam-hauled trains and goods services, the LPTB wished to focus on electrified trains and suburban traffic. Goods services were passed to theLondon and North Eastern Railway, which also took over the role of providing steam locomotives for trains beyond the end of electrification at Rickmansworth. All services north-west ofAylesbury were withdrawn by 1936[14] though services returned toQuainton Road between 1943 and 1948.[15]
The 1930s was a period of rapid growth for the north-western suburbs of London, and LPTB developed ambitious plans to simplify the Metropolitan line and expand capacity. Several stations on the Uxbridge branch were rebuilt, replacing temporary wooden buildings with modernist designs and giving Uxbridge station a new site in the town centre. A major bottleneck in the line, the double-track tunnel from Baker Street to Finchley Road, was bypassed by boring two tube tunnels underneath the Metropolitan tunnels, transferring slow services and theStanmore branch to theBakerloo line.[16] (This route was transferred to theJubilee line in 1979.)[17] In 1936, the line was extended east fromWhitechapel toBarking along the tracks of the District line.[18] London Transport inherited incompatibleelectric multiple units from the railway, including the 1927–33 multiple-unit compartment stock used on routes to Watford and Rickmansworth, and these were refurbished to form a uniform fleet and designatedLondon Underground T Stock.[19] In the 1950s,F Stock trains, with sliding doors under the control of the guard, were transferred from the District line; these mainly worked the semi-fast Harrow and Uxbridge services.[20]
A Stock vehicles at Rayners Lane in their original unpainted livery
A major rebuilding of the main line from Wembley Park to Amersham was planned in the 1930s but delayed by the war. The line from Wembley to Harrow was rebuilt immediately after the war and the project was completed from 1956 to 1962, on a more modest scale than originally planned. Until 1961, passenger trains continued to be attached to a steam locomotive atRickmansworth to run to Aylesbury. The rebuilding electrified the line from Rickmansworth to Amersham, transferring all Aylesbury services to British Railways. A pair of fast lines was added from Harrow to north of Moor Park by 1962, allowing outer-suburban trains to run fast to Moor Park.[21][failed verification] AluminiumA stock, originally unpainted, replaced the T stock and locomotive-hauled trains. More A Stock trains were built in 1962–63 to replace the trains on the Uxbridge service, giving the main line a single train type for all services. A Stock was four-car units that could operate as four- or eight-car trains;[22] normally operated as eight cars, a four-car unit operated the Chesham shuttle.[23]One person operation of the trains was proposed in 1972, but due to conflict with the trade unions was not introduced on the line until 1986.[24]
Although theEast London line had been an isolated shuttle since 1939,[18] it was shown on London Underground maps as part of the Metropolitan line until 1968.[25] In 1970, it was shown with a thin white line in the middle and labelled the "East London section".[26] By the 1985 map, it had become the "East London Line", remaining the same colour as the Metropolitan line with a white line in the middle,[27] changed to orange by the 1990 map.[28] In 1990, theHammersmith & City line became a separate line from Hammersmith to Whitechapel (Barking during the peak), the Metropolitan line being from Aldgate to Baker Street and northwards to Amersham with branches to Chesham, Uxbridge and Watford.[18][28]
On 12 December 2010, the service to Amersham was reduced from four trains per hour to two, and a direct service between Chesham and central London was introduced, replacing the 4-car Chesham to Chalfont & Latimer shuttle.[30] The final passenger services operated by the A Stock ran on 26 September 2012,[31] followed by a ticketed publicrailtour on 29 September.[32]
The Metropolitan line is 41.6 miles (67 km) long and serves 34 stations.[33] It is electrified with a four-rail DC system: a central conductor rail is energised at –250 V and a rail outside the running rail at +500 V, giving a potential difference of 750 V, except for the section from Uxbridge to Finchley Road (via Harrow-on-the-Hill) which is energised at –210 V and +420 V respectively (630 V potential difference) to maintain compatibility with1973 Stock and1996 Stock that runs in those areas.[34][35] The first 6 miles (9.7 km) fromAldgate are below ground,[36] shared with theCircle and Hammersmith & City lines to Baker Street, where the line diverges, remaining in tunnel untilFinchley Road.[37] Metropolitan line trains essentially skip two stops between Baker Street and Finchley Road, with the Jubilee line serving the intermediate stations on an adjacent parallel line. The Jubilee line then joins the Metropolitan line in the same right-of-way at Finchley Road. Metropolitan line trains then run express from Finchley Road toWembley Park, with the Jubilee line serving the intermediate stations. Metropolitan line platforms atWillesden Green andNeasden remain for emergency use.[38] At Wembley Park the Jubilee line diverges to the Stanmore branch at a grade-separated junction. From just after Finchley Road, these four tracks run parallel with theNetwork RailChiltern Main Line fromMarylebone.[37]
Between Wembley Park andHarrow-on-the-Hill, the Metropolitan is four-track, with fast and slow lines paired by direction, paralleling the two-track un-electrifiedLondon–Aylesbury line. The slow lines are between the fast lines, and the two intermediate stations have island platforms.[37] Harrow-on-the-Hill has platforms on all six lines.[37] The central slow lines diverge here at agrade-separated junction to become the 7.5 miles (12.1 km) Uxbridge branch. AfterWest Harrow, atRayners Lane the line is joined by thePiccadilly line, which shares the tracks to Uxbridge; aturnback siding allows some Piccadilly line services to terminate at Rayners Lane.[37][39]
On the main line between Harrow-on-the-Hill andMoor Park, the line is four-track, paired by use. The western fast tracks are shared with Aylesbury line services from Marylebone; the eastern slow tracks have platforms at the intermediate stations.
North of Moor Park, the Watford branch diverges from the slow lines.[37] This double-track branch has stations atCroxley andWatford.[37][40] The Watford branch has atriangle junction with the main line, with a north-facing curve betweenCroxley andRickmansworth. This route, Watford North Curve, is used daily for a few services and empty stock movements.[41]
From the Watford triangle toAmersham, the line has two tracks. AtChalfont & Latimer, the 3.89 miles (6.26 km)single-trackChesham branch diverges, running parallel to the main line for a distance.[33][37] The Metropolitan line ends at Amersham, where there are turnback sidings just beyond the platforms. The route continues toAylesbury with Chiltern Railways trains only.[42]
The fast (non-stopping) lines between Wembley Park and Harrow on the Hill are signalled with LUL signalling, but using four-aspect Network Rail signal heads.[43] The upper two lights are a two-aspect stop signal displaying either a green or red aspect, the lower two lights a repeater signal for the next stop signal ahead showing a green or yellow aspect, or no aspect when the stop signal shows a red aspect. Thus they are effectively four-light three-aspect signals with green/red/green/yellow lights from the top, danger being a single red light, caution the top green light over a yellow light, and clear two green lights.[43]
The Metropolitan line's suburban rail character opposed to other London Underground lines is also shown by the long distances between stops. Eight of the top 10 furthest apart stations on the Underground are on the Metropolitan line. The section between Chalfont & Latimer and Chesham is the longest at 3.9 miles (6.3 km),[44] whilst the Finchley Road to Wembley Park section is the second longest, and Rickmansworth to Chorleywood the fourth longest overall.
The Metropolitan line is the only London Underground line to operate non-stop services through some of its stations, although since 11 December 2011 these only run on weekdays during peak times (southbound in the morning peak, northbound in the evening peak).[45] Depending on the stopping pattern, services are advertised as eitherall-stations,semi-fast orfast on platform information boards and on-train announcements. The stopping pattern of each type of service is as follows:
All-stations services call at all stations en route[45]
Fast services run non-stop between Wembley Park and Harrow-on-the-Hill and between Harrow-on-the-Hill andMoor Park[45]
In the southbound direction,fast andsemi-fast trains do not usually call at Wembley Park, and instead run non-stop from Harrow-on-the-Hill toFinchley Road[45]
Owing to the track layout,fast services can only run to/fromAmersham orChesham. TheUxbridge branch diverges from the rest of the line before the "fast" section, while theWatford branch is not directly connected with the fast line at Moor Park.[46]
No Metropolitan line trains call at any intermediate stations between Finchley Road and Wembley Park. These stations are served by theJubilee line which runs parallel to the Metropolitan line along this section.[45]
These services combine to give a total frequency of 16tph between Baker Street and Harrow-on-the-Hill. Of these, 12tph run between Aldgate and Baker Street which, together with the 6tph frequencies on both theCircle andHammersmith & City lines,[47] gives a total of 24 trains every hour on the central-London section between Liverpool Street and Baker Street.
In the morning peak, the southbound service pattern is strengthened to the following:[45]
S8 Stock trains featuring partial transverse seating, reminiscent of the older A Stock trains
Since 20 September 2012, all services have been provided by eight-car S Stock trains[48] introduced in July 2010 to replace the 1960sA Stock.[49] Part of Bombardier'sMovia family, they have air-conditioning, feasible because the sub-surface tunnels, unlike tube tunnels, are able to disperse the exhausted hot air.[50][51] They haveregenerative brakes, returning around 20% of their energy to the network and thus reducing energy consumption.[52] With fewer seats than the older A Stock – 306 compared with 448 – they can accommodate 697 standing passengers, compared with 597 in A Stock,[note 1] and have dedicated space for wheelchairs.[53] They have a top speed of 62 miles per hour (100 km/h),[50] being the only London Underground stock to travel at that speed, doing so on the long-distance sections north of Finchley Road.
There are 58 S8 Stock trains in operation, as well as one eight-car S7 Stock also called 'S7+1' – which retains the all-longitudinal seating of the normal seven-car S7 Stock that is operated on London Underground's other sub-surface lines.
The line is served by a depot at Neasden.[note 2] The Metropolitan Railway opened a carriage works at Neasden in 1882 and the following year the locomotive works were moved from Edgware Road.[54] In 1904–05, the depot was refitted to take the new electric multiple units[55] and accommodation enlarged in 1932–3.[56] After the amalgamation into the LTPB, the depot was rebuilt from 1936 to 1939. The depot was upgraded in 2010–11 to enable it to maintain S Stock trains.[57] Trains are also stored overnight at Uxbridge, Watford, Rickmansworth and Wembley Park.[58]
In 1989, to celebrate the 100th anniversary of the opening of the Metropolitan to Chesham, the firstSteam on the Met event took place with London Underground running two weekends of steam specials between Chesham and Watford.[59] The event was a success and so in 1990 London Underground ran steam between Harrow and Amersham. In 1992, to celebrate 100 years of the Met at Amersham, the event was extended to five days at the end of May. From 1994, diesel locomotive 20227, owned by the Class 20 Locomotive Society, and electric locomotive Sarah Siddons provided air braking for the coaches.[citation needed] In 1995, trains ran between Amersham and Watford.[60]
To celebrate the 150th anniversary of the opening of the Metropolitan, special services ran in January 2013 using a restored 1892 "Jubilee" carriage, 1898–1900 Ashbury and Cravens bogie carriages, Metropolitan Railway milk van No.3,Metropolitan Railway E Class steam locomotive No. 1 and electric locomotiveSarah Siddons.[62] Further events were planned for 2013 involving Locomotive No. 1,Sarah Siddons and the Jubilee carriage, including aSteam back on the Met scheduled for May.[63]
It was planned that a new signalling system would be used first on the line north of Baker Street from the end of 2016,[64] but signalling contractor Bombardier was released from its contract by agreement in December 2013 amid heavy criticism of the procurement process[65] and London Underground subsequently awarded the contract for the project toThales in August 2015.[66]
With the introduction of S8 Stock, the track, electrical supply, and signalling systems are being upgraded in a programme planned to increase peak-hour capacity on the line by 27 per cent by the end of 2023.[64][67][68] A single control room for the sub-surface railway opened at Hammersmith on 6 May 2018, andcommunications-based train control (CBTC) provided by Thales will progressively replace 'fixed block' signalling equipment dating back the 1940s.[64][69] Trackside signals withautomatic train protection (ATP) will remain on the line north of Harrow-on-the-Hill, shared with Chiltern Railways DMUs.[64]
The rollout of CBTC has been split into sections, each known as a signal migration area (SMA).[70]
^SMAs 0.5, 1, 4–7 and 10–12 concern parts of the District, Circle, and Hammersmith & City lines.
Work on the SMAs north of Finchley Road were delayed in November 2023 because of the complexity of Neasden Depot (shared with the Jubilee Line) and challenges relating to the inter-operability withChiltern Railways which shares tracks with the Metropolitan line in this area.[71]
Resited 22 December 1865. Originally Farringdon Street, renamed Farringdon & High Holborn 1922, Farringdon 1936. Interchange for National Rail and Elizabeth line services.
Between Moor Park and Croxley, a short branch ran south-east off the Watford branch, near its junction with the main line, to Croxley Tip, a rubbish dump beside the Grand Union Canal. This site began as a gravel loading point before becoming used by the railway to dump waste such as old ballast and waste fromNeasden power station. This route, never used for passenger traffic, continued to be used by London Transport's small fleet of steam engines until 1971, when diesels replaced them. The branch closed some time after this, although a section of the spur line remained visible from a passing train.
A second short branch line, known as theHalton Railway, servedRAF Halton near Wendover, across theWendover Arm of the Grand Union Canal. The line was built during the First World War and closed in 1963.[72] The trackbed is now a footpath.[73]
Although not operated by Metropolitan passenger services, the line from South Harrow to Rayners Lane was built by the Metropolitan railway as theDistrict Railway was in financial difficulties at the time. This included a short branch, part of which is still visible, on a viaduct to a gas works. Other minor freight connections along the line once included connections to the Midland main line at Finchley Road.
A single-track spur from a small yard between Ickenham and Ruislip stations connects toRuislip Depot of the Central line. This line is used for engineering and empty stock transfers, although occasional plans suggest extending the Central line into Uxbridge by upgrading the connection. It was built in 1973.
Also known as the Croxley Rail Link, an extension to the Metropolitan line was to reroute the Watford branch from the current terminus using the disusedCroxley Green branch line toWatford Junction. Funding was agreed in December 2011[74] and the necessary permission was granted by the UK Government in July 2013.[75][40][76] Due to a funding shortfall, the project was cancelled in 2016.[76]
^Baracaia, Alexa (22 August 2006)."Seven Wonders of London".London Evening Standard. p. 21 – via newspapers.com.
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^Edwards, Dennis; Pigram, Ron (1988).The Golden Years of the Metropolitan Railway and the Metro-land Dream.Bloomsbury. p. 32.ISBN1-870630-11-4.
^Pipe, Victoria; Marshall, Geoff (2018).The Railway Adventures: Places, Trains, People and Stations. Tewkesbury: September Publishing. p. 82.ISBN9781910463871.
^abcdefgRose, Douglas (December 2007) [1980].The London Underground: A Diagrammatic History (8th ed.). London: Capital Transport.ISBN978-1-85414-315-0.
^Croome, Desmond F.; Jackson, Alan Arthur (1993).Rails Through the Clay: A History of London's Tube Railways. Capital Transport. p. 468.ISBN978-1-85414-151-4.
^"Commissioner's Report"(PDF).Board Meeting Documents. Transport for London. 20 September 2012. paragraph 3.2.Archived(PDF) from the original on 26 August 2020. Retrieved27 September 2012.
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