Standard-gauge railway

ISBN (identifier) Metre gauge 5 ft 6 in gauge railway

A standard-gauge railway is a railway with a track gauge of 1,435 mm (4 ft 8 12 in). The standard gauge is also called Stephenson gauge after George Stephenson, International gauge, UIC gauge, uniform gauge, normal gauge and European gauge in Europe.[1][2][3][4][5] It is the most widely used railway track gauge across the world, with approximately 55% of the lines in the world using it. All high-speed rail lines use standard gauge except those in Russia, Finland, Portugal and Uzbekistan. The distance between the inside edges of the rails is defined to be 1435 mm except in the United States and on some heritage British lines, where it is still defined in U.S. customary units or Imperial units as exactly "four feet eight and one half inches".[6]


As railways developed and expanded, one of the key issues was the track gauge (the distance, or width, between the inner sides of the rails) to be used. Different railways used different gauges, and where rails of different gauge met – a "gauge break" – loads had to be unloaded from one set of rail cars and re-loaded onto another, a time-consuming and expensive process. The result was the adoption throughout a large part of the world of a "standard gauge" of 1,435 mm (4 ft 8 12 in), allowing interconnectivity and interoperability.


A popular legend that has been around since at least 1937[7] traces the origin of the 1,435 mm (4 ft 8 12 in) gauge even further back than the coalfields of northern England, pointing to the evidence of rutted roads marked by chariot wheels dating from the Roman Empire.[a][8] Snopes categorised this legend as "false", but commented that "it is perhaps more fairly labelled as 'True, but for trivial and unremarkable reasons'".[9] The historical tendency to place the wheels of horse-drawn vehicles approximately 5 ft (1,524 mm) apart probably derives from the width needed to fit a carthorse in between the shafts.[9] Research however has been undertaken which supports the hypothesis that "the origin of the standard gauge of the railway might result from an interval of wheel ruts of prehistoric ancient carriages".[10]

In addition, while road-travelling vehicles are typically measured from the outermost portions of the wheel rims (and there is some evidence that the first railways were measured in this way as well),[citation needed] it became apparent that for vehicles travelling on rails it was better to have the wheel flanges located inside the rails, and thus the distance measured on the inside of the wheels (and, by extension, the inside faces of the rail heads) was the important one.

There was never a standard gauge for horse railways, but there were rough groupings: in the north of England none was less than 4 ft (1,219 mm).[11] Wylam colliery's system, built before 1763, was 5 ft (1,524 mm), as was John Blenkinsop's Middleton Railway; the old 4 ft (1,219 mm) plateway was relaid to 5 ft (1,524 mm) so that Blenkinsop's engine could be used.[12] Others were 4 ft 4 in (1,321 mm) (in Beamish) or 4 ft 7 12 in (1,410 mm) (in Bigges Main (in Wallsend), Kenton, and Coxlodge).[12][13]

The English railway pioneer George Stephenson spent much of his early engineering career working for the coal mines of County Durham. He favoured 4 ft 8 in (1,422 mm) for wagonways in Northumberland and Durham, and used it on his Killingworth line.[12] The Hetton and Springwell wagonways also used this gauge.

Stephenson's Stockton and Darlington railway (S&DR) was built primarily to transport coal from mines near Shildon to the port at Stockton-on-Tees. The initial gauge of 4 ft 8 in (1,422 mm) was set to accommodate the existing gauge of hundreds of horse-drawn chaldron wagons[14] that were already in use on the wagonways in the mines. The railway used this gauge for 15 years before a change was made to the 1,435 mm (4 ft 8 12 in) in gauge.[12][15] The historic Mount Washington Cog Railway, the world's first mountain-climbing rack railway, is still in operation in the 21st century, and has used the earlier 4 ft 8 in (1,422 mm) gauge since its inauguration in 1868.

George Stephenson used the 1,435 mm (4 ft 8 12 in) gauge (including a belated extra 12 in (13 mm) of free movement to reduce binding on curves[16]) for the Liverpool and Manchester Railway, authorised in 1826 and opened 30 September 1830. The success of this project led to Stephenson and his son Robert being employed to engineer several other larger railway projects. Thus the 4 ft 8 12 in (1,435 mm) gauge became widespread and dominant in Britain. Robert was reported to have said that if he had had a second chance to choose a standard gauge, he would have chosen one wider than 4 ft 8 12 in (1,435 mm).[17][18] "I would take a few inches more, but a very few".[19]

During the "gauge war" with the Great Western Railway, standard gauge was called narrow gauge, in contrast to the Great Western's 7 ft 14 in (2,140 mm) broad gauge. The modern use of the term "narrow gauge" for gauges less than standard did not arise for many years, until the first such locomotive-hauled passenger railway, the Ffestiniog Railway was built.


In 1845, in the United Kingdom of Great Britain and Ireland, a Royal Commission on Railway Gauges reported in favour of a standard gauge. The subsequent Gauge Act ruled that new passenger-carrying railways in Great Britain should be built to a standard gauge of 4 ft 8 12 in (1,435 mm), and those in Ireland to a new standard gauge of 5 ft 3 in (1,600 mm). In Great Britain, Stephenson's gauge was chosen on the grounds that existing lines of this gauge were eight times longer than those of the rival 7 ft or 2,134 mm (later 7 ft 14 in or 2,140 mm) gauge adopted principally by the Great Western Railway. It allowed the broad-gauge companies in Great Britain to continue with their tracks and expand their networks within the "Limits of Deviation" and the exceptions defined in the Act. After an intervening period of mixed-gauge operation (tracks were laid with three rails), the Great Western Railway finally completed the conversion of its network to standard gauge in 1892. In North East England, some early lines in colliery (coal mining) areas were 4 ft 8 in (1,422 mm), while in Scotland some early lines were 4 ft 6 in (1,372 mm). All these lines had been widened to standard gauge by 1846. The British gauges converged starting from 1846 as the advantages of equipment interchange became increasingly apparent. By the 1890s, the entire network was converted to standard gauge.

The Royal Commission made no comment about small lines narrower than standard gauge (to be called "narrow gauge"), such as the Ffestiniog Railway. Thus it permitted a future multiplicity of narrow gauges in the UK. It also made no comments about future gauges in British colonies, which allowed various gauges to be adopted across the colonies.

Parts of the United States, mainly in the Northeast, adopted the same gauge, because some early trains were purchased from Britain. The American gauges converged, as the advantages of equipment interchange became increasingly apparent. Notably, all the 5 ft (1,524 mm) broad gauge track in the South was converted to "almost standard" gauge 4 ft 9 in (1,448 mm) over the course of two days beginning on 31 May 1886.[20] See Track gauge in the United States.

In continental Europe, France and Belgium adopted a 1,500 mm (4 ft 11 116 in) gauge (measured between the midpoints of each rail's profile) for their early railways.[21] The gauge between the interior edges of the rails (the measurement adopted from 1844) differed slightly between countries, and even between networks within a country (for example, 1,440 mm or 4 ft 8 1116 in to 1,445 mm or 4 ft 8 78 in in France). The first tracks in Austria and in the Netherlands had other gauges (1,000 mm or 3 ft 3 38 in in Austria for the Donau Moldau linen and 1,945 mm or 6 ft 4 916 in in the Netherlands for the Hollandsche IJzeren Spoorweg-Maatschappij), but for interoperability reasons (the first rail service between Paris and Berlin began in 1849, first Chaix timetable) Germany adopted standard gauges, as did most other European countries.

The modern method of measuring rail gauge was agreed in the first Berne rail convention of 1886, according to the "Revue générale des chemins de fer, July 1928".

Early railways by gauge

Non-standard gauge

Almost standard gauge

Standard gauge

Dual gauge

Modern almost standard gauge railways


Country/territory Railway Notes
Albania National rail network 339 km (211 mi)[32] [33]
Algeria National rail network

Algiers Metro, Algiers tramway, Constantine tramway, Oran tramway, Oran Metro

3,973 km (2,469 mi)[34]
Angola 80 km (50 mi)ʘ
Argentina General Urquiza Railway (except for Ferrocarril Económico Correntino, which used 600 mm or 1 ft 11 58 in before its closing)
Buenos Aires Underground
Metrotranvía Mendoza
Tren de la Costa
Other major lines are mostly 1,676 mm (5 ft 6 in) broad gauge, with the exception of the 1,000 mm (3 ft 3 38 in) metre gauge General Belgrano Railway.
Australia Australian Rail Track Corporation
Pilbara Railways
Sydney Trains
Sydney Metro
Sydney Light Rail
Newcastle Light Rail
Parramatta Light Rail
NSW TrainLink
Melbourne trams
Adelaide Metro trams
Gold Coast tram
Canberra Metro
1,435 mm (4 ft 8 12 in) 2,295 km (1,426 mi)

Victoria built the first railways to the 5 ft 3 in (1,600 mm) Irish broad gauge. New South Wales then built to the standard gauge, so trains had to stop on the border and passengers transferred, which was only rectified in the 1960s. Queensland still runs on a narrow gauge but there is a standard gauge line from NSW to Brisbane.

Austria Österreichische Bundesbahnen 4,859 km (3,019 mi) The Semmering railway has UNESCO World Heritage Site status.
Bangladesh To be used only for rapid transit system, Dhaka Metro Rail 20.1 km (12.5 mi)
Belgium NMBS/SNCB, Brussels Metro and tramway 339 km (211 mi)
Bosnia and Herzegovina Željeznice Federacije Bosne i Hercegovine and Željeznice Republike Srpske,
Sarajevo tramways
1,032 km (641 mi)
Brazil Estrada de Ferro do Amapá;[35] from Uruguaiana to the border with Argentina and from Santana do Livramento to the border with Uruguay (both mixed gauge 1,435 mm and 1,000 mm or 3 ft 3 38 in metre gauge); remaining tracks at Jaguarão, Rio Grande do Sul (currently inoperable); Rio de Janeiro Light Rail; São Paulo Metro lines 4 and 5; Salvador Metro; Baixada Santista Light Rail 205.5 km (127.7 mi)
Bulgaria National Railway Infrastructure Company (NRIC),
Bulgarian State Railways (BDZ),
Sofia Underground,[36]
part of Sofia Tramway system[37]
Canada National rail network (including commuter rail operators like GO Transit, West Coast Express, AMT and Union Pearson Express). 49,422 km (30,709 mi)
The Toronto Transit Commission uses 4 ft 10 78 in (1,495 mm) gauge on one of its streetcar and subway lines.
China National rail network 103,144 km (64,091 mi)
Croatia Hrvatske Željeznice
Colombia Metro de Medellín, Tren del Cerrejón, Metro de Bogotá
Cuba Ferrocarriles de Cuba 4,266 km (2,651 mi)
Czech Republic Správa železniční dopravní cesty,
Prague Metro,
all tram systems in the country (Liberec has dual gauge 1,000/1,435 mm, with one metre-gauge interurban line to Jablonec nad Nisou),
funicular in Prague
9,478 km (5,889 mi)
Denmark Banedanmark and Copenhagen Metro
Djibouti Addis Ababa-Djibouti Railway 100 km (62 mi)
Egypt Egyptian National Railways
Estonia Rail Baltica Standard-gauge Rail Baltica project is in design and engineering stage. Projected opening in 2026.
Ethiopia Addis Ababa-Djibouti Railway; Addis Ababa Light Rail 659 km (409 mi) Other standard gauge lines under construction.
Finland Rail Baltica; Under construction: Tampere tram
Planned: Helsinki–Tallinn Tunnel
France SNCF, RATP (on RER lines)
Gabon Trans-Gabon Railway 669 km
Germany Deutsche Bahn, numerous local public transport providers 43,468 km (27,010 mi)
Greece Hellenic Railways Organisation (operated by TrainOSE) All modern Greek network, except in the Peloponnese
Holy See 1 km (0.62 mi)
Hong Kong MTR (former KCR network – East Rail Line, West Rail Line, Ma On Shan Line, Light Rail) Other MTR lines use 1,432 mm (4 ft ​8 38 in) instead of 4 ft ​8 12 in[38][39][40]
Hungary MÁV, GySEV,
Budapest metro, HÉV (Suburban railway),
Tram systems in Budapest, Debrecen, Miskolc, Szeged,
Budapest Cog-wheel Railway
India Only used for rapid transit and tram, Bangalore Metro, Chennai Metro, Delhi Metro (Phase 2 onwards), Rapid Metro Gurgaon, Hyderabad Metro, Jaipur Metro, Kochi Metro, Kolkata Metro (Line 2 onwards), Lucknow Metro, Mumbai Metro, Navi Mumbai Metro and Trams in Kolkata. The under construction Mumbai–Ahmedabad high-speed rail corridor based on the Shinkansen also uses standard gauge. All of the under-construction and future rapid transit systems would be in standard gauge. Indian nationwide rail system (Indian Railways) uses 1,676 mm (5 ft 6 in) broad gauge.
Indonesia Railways in Aceh Province and Celebes. Light railways in Greater Jakarta (Jakarta LRT and LRT Jabodebek). Rest of the country uses 1,067 mm (3 ft 6 in).
Iran Islamic Republic of Iran Railways 12,998 km (8,077 mi)
Iraq Iraqi Republic Railways 485 km (301 mi)
Ireland Railway Procurement Agency Luas in Dublin
Israel Israel Railways, CTS, operating the Jerusalem Light Rail
Italy Ferrovie dello Stato 16,723 km (10,391 mi)
Japan Shinkansen, JR Hokkaido Naebo Works (see Train on Train), Keisei Line, Keikyu Line, Tokyo Metro (Ginza and Marunouchi lines), Toei Subway (Asakusa and Oedo lines), Kintetsu Railway (Osaka, Nara, Nagoya, Yamada, Kyoto, and Keihanna lines and their associated branches), Keihan Railway, Hankyu Railway, Hanshin Railway, Kyoto Municipal Subway, Kobe Municipal Subway, Osaka Metro, Kita-Osaka Kyuko Railway, Fukuoka City Subway (Nanakuma Line), Sendai Subway (Tozai Line), Nagoya Municipal Subway (Higashiyama, Meijō, and Meikō lines), Nose Electric Railway, Yokohama Municipal Subway (Blue and Green lines) 4,251 km (2,641 mi), all electrified
Kenya Mombasa-Nairobi Standard Gauge Railway 485 km (301 mi) Inaugurated May 31, 2017. An extension from Nairobi to Naivasha is under construction. A further extension east to the Ugandan border is planned.
Latvia Rail Baltica Standard-gauge Rail Baltica project is in design and engineering stage. Projected opening in 2026.
Lebanon All lines out of service and essentially dismantled
Libya Network under construction
Lithuania Rail Baltica First phase, from Kaunas to the Polish border, completed in 2015. Second phase, from Kaunas north to Tallinn, Estonia, is at planning stage.
Luxembourg Société Nationale des Chemins de Fer Luxembourgeois
Malaysia RapidKL (Kelana Jaya Line, Ampang Line, MRT Kajang Line,
MRT Sungai Buloh-Serdang-Putrajaya Line), KLIA Ekspres,
MRL East Coast Rail Link (under construction), Kuala Lumpur–Singapore High Speed Rail (planned)
998 km (620 mi)
Mexico[41] 24,740 km (15,370 mi)
Montenegro Željeznice Crne Gore 3
Morocco Rail transport in Morocco 2,067 km (1,284 mi)
Netherlands Nederlandse Spoorwegen and regional railways.
Nigeria Lagos–Kano Standard Gauge Railway; Lagos Rail Mass Transit Under construction; Abuja to Kaduna section operational.
North Korea Railways of the DPRK.
North Macedonia Macedonian Railways
Norway Norwegian National Rail Administration, Rail transport in Norway 4,087 km (2,540 mi)
Pakistan To be used only for rapid transit system, Lahore Metro[42] Pakistan's nationwide rail system (Pakistan Railways) uses 1,676 mm (5 ft 6 in) broad gauge. Any future additions to this system would also be in broad gauge.
Panama Panama Railway; Panama Metro Regauged from 5 ft (1,524 mm) in 2001
Paraguay Ferrocarril Presidente Don Carlos Antonio López, now Ferrocarril de Paraguay S.A. (FEPASA) 36 km out of Asunción (used as a tourist steam line), plus 5 km from Encarnación to the border with Argentina, carrying mainly exported soy; the rest of the 441-km line awaits its fate, while redevelopment plans come and go with regularity. The section from west of Encarnación to north of San Salvador, plus the entire San Salvador–Abaí branch, have been dismantled by the railway itself and sold for scrap to raise funds.
Peru Railway Development Corporation,[43] Ferrocarril Central Andino (Callao–Lima–La Oroya–Huancayo and La Oroya–Cerro del Pasco lines), Ferrocarril del sur de Peru (operated by Peru Rail) Matarani–ArequipaPuno and Puno–Cuzco, Ilo–Moquegua mining railway, Tacna–Arica (Chile) international line, (operated by Tacna Province), Lima electric suburban railway 1,603 km (996 mi)
Philippines Present: Manila LRT and MRT
Proposed: Philippine National Railways network, Manila LRT and MRT extensions, Cebu LRT
50.3 km (31.3 mi), all electrified as of 2010.
The Philippine National Railways will convert its network from 1,067 mm (3 ft 6 in). All future lines will be in standard gauge.[44] At least 4,000 km (2,500 mi) of new track will be built, in which 646 km (401 mi) will be electrified.
Poland Polskie Koleje Państwowe, Warsaw Metro, most tramway systems throughout the country
Portugal Planned high-speed lines, Braga and Oporto (Guindais) funiculars, Lisbon Metro, Oporto Metro (partly adapted from former 1,000 mm (3 ft 3 38 in) metre gauge; tracks), Metro Transportes do Sul light rail in Almada. All other railways use 1,668 mm (5 ft 5 2132 in) (broad gauge); some use 1,000 mm (3 ft 3 38 in) metre gauge; Decauville uses 500 mm (19 34 in) gauge.
rail Baltica Poland-Lithuania-Latvia-Estonia-Finland. 870 km (540 mi)
Romania Căile Ferate Române, Bucharest Metro,
Tram systems in Botoşani, Iaşi, Brăila, Bucharest, Cluj-Napoca, Craiova, Galaţi, Oradea, Ploieşti and Timișoara
Russia Rostov-on-Don tramway, lines connecting Kaliningrad with Poland
Rwanda Isaka–Kigali Standard Gauge Railway 150 km (93 mi) New railway between Kigali and the Tanzanian town of Isaka is planned.
Saudi Arabia Rail transport in Saudi Arabia
Serbia Serbian Railways
Singapore MRT, Kuala Lumpur–Singapore High Speed Rail (planned)
Slovakia Železnice Slovenskej republiky, Košice tramway system
Slovenia Slovenske železnice
Senegal 80 km (50 mi)
South Africa Gautrain in Gauteng Province. Rest of country uses 1,067 mm (3 ft 6 in) 80 km (50 mi)
South Korea KRNA
Spain AVE high-speed rail lines from Madrid to Seville, Málaga, Saragossa, Barcelona (-Perthus), Toledo, Huesca, and Valladolid, Barcelona Metro (L2, L3, L4, and L5 lines), Barcelona FGC (lines L6 and L7), and Metro Vallès (lines S1, S2, S5, and S55).
| All other railways use 1,668 mm (5 ft 5 2132 in) (broad gauge) and/or 1,000 mm (3 ft 3 38 in) metre gauge.
2,571 km (1,598 mi)
Sweden Swedish Transport Administration, Storstockholms Lokaltrafik (Stockholm metro, commuter and light rail lines), tram networks in Gothenburg and Norrköping
Switzerland Swiss Federal Railways,

BLS, Rigi Railways (rack railway)

SFR 3,134 km in standard gauge and 98 km metre gauge [45]

449 km

Syria Chemins de Fer Syriens 2,052 km (1,275 mi)
Taiwan Taipei Rapid Transit System, Taiwan High Speed Rail, and Kaohsiung Mass Rapid Transit 566 km (352 mi)
Tanzania Tanzania Standard Gauge Railway 202 km (126 mi) line from Dar es Salaam to Morogoro under construction. Contract awarded in 2019 for a 422 km (262 mi) extension from Morogoro to Makutupora.
Thailand BTS Skytrain, MRT, and Suvarnabhumi Airport Link
The State Railway of Thailand uses 1,000 mm (3 ft 3 38 in).
80 km (50 mi)
Tunisia Northern part of the network 471 km (293 mi)
Turkey Turkish State Railways (also operates Marmaray), metro networks, and tram networks Some tram networks use 1,000 mm (3 ft 3 38 in) metre gauge.
Uganda Uganda Standard Gauge Railway Railway line from Kampala to the Kenyan border is planned.
United Arab Emirates Rail transport in the United Arab Emirates
United Kingdom (Great Britain) Entire rail network in Great Britain (but not Ireland) since standardisation by the Regulating the Gauge of Railways Act 1846 Also used on all metro and tramway systems with the exception of the self-contained Glasgow Subway, which is 4 ft (1,219 mm).
United States Modern national railroad network; see Track gauge in the United States

The Washington Metro uses 4 ft 8 14 in (1,429 mm) gauge, which is 6 mm (0.24 in) narrower than standard gauge.
The Bay Area Rapid Transit system uses 5 ft 6 in Indian gauge.

129,774 km (80,638 mi)
Uruguay National rail network 2,900 km (1,800 mi)
Vietnam North of Hanoi[46] 178 km (111 mi). Includes dual gauge (standard/metre) to the Chinese border.

Non-rail use

Several states in the United States had laws requiring road vehicles to have a consistent gauge to allow them to follow ruts in the road. Those gauges were similar to railway standard gauge.[47]

See also


  1. ^ The gaps in the pedestrian crossings in Pompeii could give credence or otherwise to this statement, but no relevant studies appear to have been made.


  1. ^ Francesco FALCO (31 December 2012). "2007-ee-27010-s". TEN-T Executive Agency. Archived from the original on 27 February 2012. Retrieved 20 August 2013.
  2. ^ "Japan". 1 October 1964. Archived from the original on 29 June 2012. Retrieved 20 August 2013.
  3. ^ Francesco FALCO (23 January 2013). "EU support to help convert the Port of Barcelona's rail network to UIC gauge". TEN-T Executive Agency. Archived from the original on 11 February 2013. Retrieved 20 August 2013.
  4. ^ "Spain: opening of the first standard UIC gauge cross-border corridor between Spain and France". UIC Communications. Retrieved 20 August 2013.
  5. ^ "Displaceable rolling bogie for railway vehicles". Archived from the original on 29 June 2013. Retrieved 20 August 2013.
  6. ^ [1] Thirty-Seventh Congress Session III Chap CXII March 3, 1863 Retrieved on 2019-01-08.
  7. ^ "Standard Railway Gauge". Townsville Bulletin. 5 October 1937. p. 12. Retrieved 3 June 2011 – via National Library of Australia.
  8. ^ "Standard Rail Gauge Set By Old Ox-Carts". The Worker. 58 (3122). Queensland. 19 May 1947. p. 17. Retrieved 13 April 2016 – via National Library of Australia.
  9. ^ a b "Railroad Gauges and Roman Chariots". Urban Legends Reference Pages.
  10. ^ Ogata et al. (2006), p. 98
  11. ^ 1966, p. 56.
  12. ^ a b c d Baxter 1966, p. 56.
  13. ^ "Tyne and Wear HER(1128): Bigges Main Wagonway - Details". Archived from the original on 21 November 2016. Retrieved 20 November 2016.
  14. ^ "The Wagons". DRCM. Retrieved 1 June 2016.
  15. ^ Vaughan (1997).[page needed]
  16. ^ Vaughan 1977.
  17. ^ "Trans-Australian Railway. Bill Before The Senate". Western Mail (Western Australia). Perth. 2 December 1911. p. 17. Retrieved 15 March 2013 – via National Library of Australia.
  18. ^ "Peoples' Liberal Party". Bendigo Advertiser. 27 February 1912. p. 5. Retrieved 21 November 2013 – via National Library of Australia.
  19. ^ Jones (2009), pp. 64–65.
  20. ^ "The Days They Changed the Gauge". Retrieved 1 June 2016.
  21. ^ Auguste Perdonnet, mémoire sur les chemins à ornières, 1830
  22. ^ Whishaw (1842), p. 91.
  23. ^ "Public transport in and about the parish". London: St George-in-the-East Church. London and Blackwall Railway; London, Tilbury & Southend Railway.
  24. ^ "Document" (PDF). Mernick. Retrieved 1 June 2016.
  25. ^ Whishaw (1842), p. 260.
  26. ^ Whishaw (1842), p. 363.
  27. ^ a b Jones (2013), p. 33.
  28. ^ Whishaw (1842), p. 319.
  29. ^ Whishaw (1842), p. 54.
  30. ^ Whishaw (1842), p. 273.
  31. ^ Whishaw (1842), p. 303.
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  33. ^ CIA data
  34. ^ "The World Factbook". Retrieved 1 June 2016.
  35. ^ Setti (2008), p. 25.
  36. ^ "Archived copy". Archived from the original on 18 August 2009. Retrieved 7 December 2011.CS1 maint: archived copy as title (link)
  37. ^ "". Archived from the original on 10 August 2006. Retrieved 1 June 2016. External link in |title= (help)
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  39. ^ "Archived copy". Archived from the original on 9 June 2013. Retrieved 7 December 2011.CS1 maint: archived copy as title (link)
  40. ^ Allen (1987).[page needed]
  41. ^ "Mexlist". 2007. Retrieved 29 November 2007.
  42. ^ "SECTION - 3 DESCRIPTION OF THE PROJECT" (PDF). EIA of Construction of Lahore Orange Line Metro Train Project (Ali Town –Dera Gujran). Environmental Protection Department. Retrieved 25 January 2017.
  43. ^ "Ferrocarril Central Andino". Railroad Development Corporation. 2007. Retrieved 29 November 2007.
  44. ^ "Philippines approves standard gauge for all new lines". 10 August 2016. Retrieved 12 July 2020.
  45. ^ "Infrastructures". SBB CFF FFS. 2018. Retrieved 21 July 2019.
  46. ^ "Railway Infrastructure". Vietnam Railways. 2005. Archived from the original on 18 April 2010. Retrieved 29 November 2007.
  47. ^ "The Narrow-Gauge Question". The Argus. Melbourne. 2 October 1872. Retrieved 14 April 2012 – via