Editing London Post Office Railway (section)

==History==
===Use as post office railway===
{{London Post Office Railway}}
In 1911, a plan evolved to build an underground railway {{convert|6+1/2|mi|km}} long<ref>Romance of London's Underground, Ayer Publishing</ref> from [[Paddington]] to [[Whitechapel]] serving the main sorting offices along the route; road traffic congestion was causing unacceptable delays. The contract to build the tunnels was won by [[Mowlem|John Mowlem and Co]].<ref>{{cite web|url=http://www.time-capsules.co.uk/picture/number2132.asp|title=Sign in to Photo Forums|website=www.time-capsules.co.uk}}</ref> Construction of the tunnels started in February 1915 from a series of shafts. Most of the line was constructed using the [[Tunnelling shield|Greathead shield system]], with limited amounts of hand-mining for connecting tunnels at stations.

The main line has a single {{convert|9|ft|adj=on}} diameter tube with two tracks. Just before stations, tunnels diverge into two single-track {{convert|7|ft|adj=on}} diameter tunnels leading to two parallel {{convert|25|ft|adj=on}} diameter station tunnels. The main tube is at a depth of around {{convert|70|ft}}.<ref>{{cite magazine| title=London's Post-Office Railway| date =  March 1952| page =164|volume= 97| number= 3| issn = 0032-4558|magazine = [[Popular Mechanics]]| publisher =[[Hearst Magazines]]|url=https://books.google.com/books?id=yNwDAAAAMBAJ&pg=PA164}}</ref> Stations are at a much shallower depth, with a 1-in-20 gradient into the stations. The gradients assist in slowing the trains when approaching stations, and accelerating them away. There is also less distance to lift mail from the stations to the surface. At [[Oxford Circus]] the tunnel runs close to the [[Bakerloo line]] tunnel of the [[London Underground]]. The tunnel also runs under [[Selfridges]] as the recent 2018 refurbishment of the building revealed.<ref>{{cite web | url=https://www.ajbuildingslibrary.co.uk/projects/display/id/8258 | title=Selfridges London &#124; AJ Buildings Library }}</ref>

[[File:London Post Office Railway Map.jpg|thumb|Map of the Post Office Railway]]
During 1917, work was suspended due to the shortage of labour and materials. By June 1924, track laying had started. In February 1927, the first section, between Paddington and the West Central District Office, was made available for training. The line became available for the Christmas parcel post in 1927 and letters were carried from February 1928.

In 1954, plans were developed for a new Western District Office at Rathbone Place, which required a diversion, opening in 1958.<ref>New Tunnels for Post Office Railway ''[[Railway Gazette International|Railway Gazette]]'' 25 April 1958 page 495</ref><ref>{{Cite journal | last1 = Blackford | first1 = S. | last2 = Cuthbert | first2 = E. W. | doi = 10.1680/iicep.1960.11893 | title = Underground Station for Western District Post Office, London. (Includes Plate) | journal = ICE Proceedings | volume = 15 | issue = 2 | pages = 81 | year = 1960 }}</ref><ref>{{Cite journal | last1 = Collingridge | first1 = V. H. | last2 = Tuckwell | first2 = R. E. | doi = 10.1680/iicep.1960.11897 | title = Underground Station for Western District Post Office, London. (Includes Plates) | journal = ICE Proceedings | volume = 15 | issue = 2 | pages = 95 | year = 1960 }}</ref> It was not until 3 August 1965 that the new station and office were opened by the [[Postmaster General of the United Kingdom|Postmaster General]], [[Tony Benn]]. The disused section was used as a store tunnel; some parts of it still have the track in place.

In 1987, the railway changed its name to Mail Rail in celebration of its 60th anniversary, and some trains were rebuilt with more aerodynamic casings.<ref name="story"/>

===Closure===
A [[Royal Mail]] press release in April 2003 said that the railway would be closed and mothballed at the end of May that year. Royal Mail had earlier stated that using the railway was five times more expensive than using road transport for the same task. The [[Communication Workers Union (United Kingdom)|Communication Workers Union]] claimed the actual figure was closer to three times more expensive but argued that this was the result of a deliberate policy of running the railway down and using it at only one-third of its capacity. A local governmental report by the [[Greater London Authority]] stated that the "line carries an average of four million letters and parcels per day" and was in support of continued use and criticized the increase of lorries on local roads, estimated to be 80 more truck loads per week.<ref>{{Cite web|url=https://www.london.gov.uk/sites/default/files/gla_migrate_files_destination/archives/assembly-reports-pubserv-mailrail.pdf|title=The future of Mail Rail|author=London Assembly's Public Services Committee|website=Greater London Assembly}}</ref> The railway was closed on 31 May 2003.<ref name="finalcall"/><ref>End of the line for Mail Rail ''[[Today's Railways UK|Entrain]]'' issue 19 July 2003 page 12</ref>

In April 2011, an [[urban exploration]] group called the "Consolidation Crew" published accounts of illicit access to the tunnels. Detailed photography and text revealed that the railway is still largely in good condition, despite some natural decay.<ref>{{cite web |url=http://www.placehacking.co.uk/2011/04/24/security-breach-london-mail-rail/ |title=Security-Breach: London Mail Rail|publisher=placehacking.co.uk |archive-url=https://web.archive.org/web/20110429171845if_/http://www.placehacking.co.uk/2011/04/24/security-breach-london-mail-rail/ |archive-date=2011-04-29 |access-date=2021-04-25 }}</ref><ref>{{cite web |url=http://www.silentuk.com/?p=2792 |title=The Post Office Railway (Mail Rail)|publisher=silentuk.com |archive-date=23 April 2011|url-status=usurped |archive-url=https://web.archive.org/web/20110423152336/http://www.silentuk.com/?p=2792|access-date=20 April 2011|date=18 April 2011 }}</ref> More recently, media have been admitted to the tunnels as part of the pre-launch publicity for the Postal Museum. Photographs show much of the infrastructure in place.<ref>{{cite web|title=Eight storeys down on abandoned tracks|url=http://leftoverlondoner.tumblr.com/post/160455903728/eight-storeys-down-on-abandoned-tracks|website=Leftover London|access-date=10 May 2017}}</ref>

A team from the [[University of Cambridge]] has taken over a short, double track section of unused Post Office tunnel near [[Liverpool Street Station]], where a newly built tunnel for [[Crossrail]] is situated some two metres beneath. The study is to establish how the original [[cast-iron]] lining sections, which are similar to those used for many miles of railway under London, resist possible deformation and soil movement caused by the new works. [[Digital camera]]s, [[Brillouin scattering#Fiber Optic Sensing|fibre optic deformation sensors]], [[laser scanner]]s and other low-cost instruments, reporting in [[Real-time computing|real time]], have been installed in the vacated tunnel. As well as providing information about the behaviour of the old construction materials, the scheme can also provide an early warning if the new tunnel bores are creating dangerous soil movement.<ref>{{cite web|title=Bridging the Knowledge Gap in London's 'Secret Tube'|url=http://www-smartinfrastructure.eng.cam.ac.uk/news/20140613BCIawardshortlist|publisher=Cambridge Centre for Smart Infrastructure & Construction|access-date=16 June 2014}}</ref>

===Redevelopment and preservation===
[[File:All Aboard the Mail Rail (44303391761).jpg|thumb|Tour carriages on the Mail Rail at the Postal Museum]]
In October 2013, the [[Postal Museum, London|British Postal Museum & Archive]] announced that it intended opening part of the network to the public.<ref>{{cite news|url=https://www.bbc.co.uk/news/magazine-25918218|publisher=[[BBC News]]|title=Mail Rail: The hidden trains under London's streets}}</ref><ref>{{cite web|url=http://postalmuseum.org/mail-rail|publisher=[[Postal Museum, London|British Postal Museum & Archive]]|title=Mail Rail}}</ref> After approval was granted by [[Islington London Borough Council|Islington Council]], work on the new museum and the railway began in 2014.<ref>{{cite magazine|url=https://www.wired.co.uk/news/archive/2014-03/14/mail-rail|title=Ride London's abandoned underground 'Mail Rail'|last=Solon|first=Olivia|date=14 March 2014|magazine=Wired UK|access-date=8 June 2014}}</ref> Special tourist trains were installed in late 2016. It was planned to open a circular route, running beneath the depot at Mount Pleasant with a journey time of around 15 minutes, by mid-2017.<ref>{{cite web|url=https://www.postalmuseum.org/discover/attractions/mail-rail-ride/|title=Ride Mail Rail - The Postal Museum -}}</ref><ref>{{cite web|url=https://www.theguardian.com/travel/2017/jul/28/mail-rail-underground-london-postal-museum|title=Mail Rail delivers an underground history lesson at London's new Postal Museum|first=Priya|last=Khaira-Hanks|date=28 July 2017|work=[[The Guardian]]}}</ref><ref>{{Cite news|url=https://postalmuseum.org/discover/attractions/|title=Attractions {{!}} The Postal Museum {{!}} Opening July 2017|work=The Postal Museum|access-date=2017-04-24|language=en-US}}</ref> The museum opened on 5 September.<ref>{{Cite news|url=https://www.theguardian.com/uk-news/2017/sep/02/engineer-lends-voice-to-mail-rail-tours-as-secret-world-opens-to-public|title=Engineer lends voice to Mail Rail tours as secret world opens to public|last=Kennedy|first=Maev|date=2017-09-02|work=The Guardian|access-date=2017-09-06|language=en-GB|issn=0261-3077}}</ref>

In its first year of operation (2017&ndash;2018), the trains performed 9,000 trips totalling {{convert|6213|mi|-1}}, with the railway and museum hosting over 198,000 visitors.<ref>{{cite magazine |editor1-last=Milner |editor1-first=Chris |title=Rail Mail's first year of success |magazine=[[The Railway Magazine]] |date=October 2018 |volume=164 |issue=1,411 |page=10 |publisher=Mortons Media |location=Horncastle |issn=0033-8923}}</ref>