Astandard-gauge railway is arailway with atrack gauge of1,435 mm (4 ft 8+1⁄2 in). The standard gauge is also calledStephenson gauge (afterGeorge Stephenson),international gauge,UIC gauge,uniform gauge,normal gauge in Europe,[1][2][3][4][5] andSGR in East Africa. It is the most widely used track gauge around the world, with about 55% of the lines in the world using it.
Allhigh-speed rail lines use standard gauge exceptthose in Russia,Finland,Uzbekistan, and some line sections inSpain.[6] The distance between the inside edges of the heads of the rails is defined to be 1,435 mm except in the United States, Canada, and on some heritage British lines, where it is defined inU.S. customary/British Imperial units as exactly "four feet eight and one half inches",[7] which is equivalent to 1,435.1mm.
Asrailways developed and expanded, one of the key issues was thetrack gauge (the distance, or width, between the inner sides of the rail heads) to be used, as the wheels of therolling stock (locomotives, cars, etc.) must match this distance. Different railways used different gauges, and where track of different gauges met – a "gauge break" – loads had to be unloaded from one set of rail cars and reloaded onto another, a time-consuming and expensive process. The result was the adoption throughout a large part of the world of a "standard gauge" of1,435 mm (4 ft 8+1⁄2 in), allowing interconnectivity and interoperability.
A popular legend that has circulated since at least 1937[8] traces the origin of the1,435 mm (4 ft 8+1⁄2 in) gauge even further back than the coalfields of northern England, pointing to the evidence of rutted roads marked bychariot wheels dating from theRoman Empire.[a][9]Snopes categorised this legend as "false", but commented that it "is perhaps more fairly labeled as 'Partly true, but for trivial and unremarkable reasons.'"[10] The historical tendency to place the wheels of horse-drawn vehicles around5 ft (1,524 mm) apart probably derives from the width needed to fit acarthorse in between the shafts.[10] Research, however, has been undertaken to support the hypothesis that "the origin of the standard gauge of the railway might result from an interval of wheel ruts of prehistoric ancient carriages".[11]
In addition, while road-travelling vehicles are typically measured from the outermost portions of the wheel rims, it became apparent that for vehicles travelling on rails, having mainwheel flanges that fitinside the rails is better, thus the minimum distance between the wheels (and, by extension, the inside faces of therail heads) was the important one.
A standard gauge for horse railways never existed, but rough groupings were used; in the north of England none was less than4 ft (1,219 mm).[12]Wylam colliery's system, built before 1763, was5 ft (1,524 mm), as wasJohn Blenkinsop'sMiddleton Railway; the old4 ft (1,219 mm) plateway was relaid to5 ft (1,524 mm) so that Blenkinsop's engine could be used.[12] Others were4 ft 4 in (1,321 mm) (inBeamish) or4 ft 7+1⁄2 in (1,410 mm) (inBigges Main (inWallsend),Kenton, andCoxlodge).[12][13]
Very early tramways used pairs of stone blocks which meant that the feet of horses didn't trip over obstacles in the middle of the track. However timber sleepers,which could cause the feet of horses to trip, held the gauge better.
Stephenson'sStockton and Darlington railway (S&DR) was built primarily to transport coal from mines nearShildon to the port atStockton-on-Tees. Opening in 1825, the initial gauge of4 ft 8 in (1,422 mm) was set to accommodate the existing gauge of hundreds of horse-drawnchaldron wagons[14] that were already in use on thewagonways in the mines. The railway used this gauge for 15 years before achange was made, debuting around 1850, to the1,435 mm (4 ft 8+1⁄2 in) gauge.[12][15][page needed] The historicMount Washington Cog Railway, the world's firstmountain-climbingrack railway, is still in operation in the 21st century, and has used the earlier4 ft 8 in (1,422 mm) gauge since its inauguration in 1868.
George Stephenson introduced the1,435 mm (4 ft 8+1⁄2 in) gauge (including a belated extra1⁄2 in (13 mm) of free movement to reduce binding on curves[16]) for theLiverpool and Manchester Railway, authorised in 1826 and opened 30 September 1830. The extra half inch was not regarded at first as very significant, and some early trains ran on both gauges daily without compromising safety.[17]
The success of this project led to Stephenson and his sonRobert being employed to engineer several other larger railway projects. Thus the4 ft 8+1⁄2 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 gauge, he would have chosen one wider than4 ft 8+1⁄2 in (1,435 mm).[18][19] "I would take a few inches more, but a very few".[20]
In 1845, in theUnited Kingdom of Great Britain and Ireland, aRoyal Commission on Railway Gauges reported in favour of a standard gauge. The subsequentGauge Act ruled that new passenger-carrying railways in Great Britain should be built to a standard gauge of4 ft 8+1⁄2 in (1,435 mm), and those in Ireland to a new standard gauge of5 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 rival7 ft or2,134 mm (later7 ft 1⁄4 in or2,140 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 ofmixed-gauge operation (tracks were laid with three rails), the Great Western Railway finally completed theconversion of its network to standard gauge in 1892. In North East England, some early lines in colliery (coal mining) areas were4 ft 8 in (1,422 mm), while inScotland some early lines were4 ft 6 in (1,372 mm). The British gauges converged starting from 1846 as the advantages of equipment interchange became increasingly apparent. By the 1890s, the entire network wasconverted to standard gauge.
TheRoyal Commission made no comment about small lines narrower than standard gauge (to be called "narrow gauge"), such as theFfestiniog 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 the5 ft (1,524 mm)broad gauge track in theSouth was converted to "almost standard" gauge4 ft 9 in (1,448 mm) over the course of two days beginning on 31 May 1886.[22]SeeTrack gauge in the United States.
In continental Europe, France and Belgium adopted a1,500 mm (4 ft 11+1⁄16 in) gauge (measured between the midpoints of eachrail's profile) for their early railways.[23] 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 or4 ft 8+11⁄16 in to1,445 mm or4 ft 8+7⁄8 in in France). The first tracks in Austria and in the Netherlands had other gauges (1,000 mm or3 ft 3+3⁄8 in in Austria for the Donau Moldau line and1,945 mm or6 ft 4+9⁄16 in in the Netherlands for theHollandsche 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.[24]
Thetrams in Nuremberg nominally used1,432 mm (4 ft 8+3⁄8 in) during much of their existence, but have since beenconverted to standard gauge in name as well as fact.
All the early French railways (including Saint-Etienne Andrezieux, authorised 1823, opened 1827) had a French Gauge of1,500 mm (4 ft 11+1⁄16 in) from rail axis to rail axis, compatible with early standard gaugetolerances)
Thetrams in Dresden, authorised in 1872 ashorsecars, used1,440 mm (4 ft 8+11⁄16 in) gauge vehicles. Converted to 600 V DC electric trams in 1893, they now use1,450 mm (4 ft 9+3⁄32 in); both gauges are within thetolerance for standard gauge.
Victoria built the first railways to the5 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 fromNSW to Brisbane.
Estrada de Ferro do Amapá;[40] from Uruguaiana to the border with Argentina and from Santana do Livramento to the border with Uruguay (bothmixed gauge1,435 mm and1,000 mm or3 ft 3+3⁄8 inmetre gauge); remaining tracks at Jaguarão, Rio Grande do Sul (currently inoperable)
alltram systems in the country (Liberec has dual gauge 1,000/1,435 mm, with one metre-gauge only for heritage rolling stock on a small part of the network)
Standard-gauge Rail Baltica railway is under construction and is scheduled to be completed by 2030. Cost studies have been undertaken for a potential overhaul of entire rail network to standard gauge.[43]
The very first railway line in Indonesia which connectsSemarang to Tanggung, which later extended toYogyakarta was laid to standard gauge.[47] Opened in 1867, it was mostly regauged to 1,067mm/3ft6in duringJapanese occupation in 1943, while a short line in Semarang Harbor soldiered on until 1945.[48] Standard gauge railway lines made a return in 2014 on experimental railway line in Aceh.
The railway tracks of Java and Sumatra use1,067 mm (3 ft 6 in).
485 km (301 mi) Inaugurated 31 May 2017. An extension fromNairobi toNaivasha is under construction. A further extension east to theUgandan border is planned.
First phase, fromKaunas to the Polish border, completed in 2015. The second phase, from Kaunas north to Tallinn and from Kaunas to Vilnius, is in the design and construction phase and scheduled to be completed by 2030.
Pakistan's nationwide rail system (Pakistan Railways) uses1,676 mm (5 ft 6 in) broad gauge. Any future additions to this system would also be in broad gauge.
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.
Railway Development Corporation,[52] 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–Arequipa–Puno and Puno–Cuzco, Ilo–Moquegua mining railway, Tacna–Arica (Chile) international line, (operated by Tacna Province), Lima electric suburban railway
AVEhigh-speed rail lines from Madrid to Seville, Málaga, Alicante, Saragossa, Barcelona (-Perthus), Orense, Toledo, Huesca, León and Valladolid,Barcelona Metro (L2,L3,L4, andL5 lines), Barcelona FGC (linesL6 andL7), and Metro Vallès (linesS1,S2,S5, andS55)
300 km (186 mi) line from Dar es Salaam to Morogoro has been completed in April 2022 currently in live testing phase.[63] Contract awarded in 2019 for a 422 km (262 mi) extension from Morogoro to Makutupora.
Several states in the United States had laws requiring road vehicles to have a consistentgauge to allow them to follow ruts in the road. Those gauges were similar to railway standard gauge.[65]
^The gaps in the pedestrian crossings inPompeii could give credence or otherwise to this statement, but no relevant studies appear to have been made.
^For the Philippine National Railways, 2,278 km (1,415 mi) for the Mindanao Railway, 296 km (184 mi) for theNorth–South Commuter Railway (NSCR),[54] 298 km (185 mi) for NSCR extensions,[55] 92 km (57 mi) for the Northeast Commuter Line toCabanatuan,[56][57] 581 to 639 km (361 to 397 mi) for the South Main Line rehabilitation, 71 km (44 mi) for the Subic–Clark Railway, 244 km (152 mi) for theSan Jose–Tuguegarao line,[58] and 175 km (109 mi) for the Tarlac–San Fernando line.[59] Proposed MRT lines have a total length of 370 km (230 mi), discounting the MonorailLine 4.LRT Line 1 extension is 26 km (16 mi),[60] while LRT Line 6's total proposed track length is 169 km (105 mi).[61] All figures mentioned denote track length, not line or system length.
^Tomlinson, Wiliam Weaver (1915).The North Eastern Railway: Its Rise and Development. Newcastle-upon-Tyne; London: Andrew Reid; Longmans, Green. p. 81. Retrieved20 March 2023.I [John Dixon] can testify to the fact of there being half an inch difference in the gauge of theGreat North of England Railway and the Stockton and Darlington Railway, and that engines and carriages reciprocally travel on each line daily without danger or a suspicion thereof from that cause: indeed, the fact of this difference is not generally known.
^"SECTION - 3 DESCRIPTION OF THE PROJECT"(PDF).EIA of Construction of Lahore Orange Line Metro Train Project (Ali Town –Dera Gujran). Environmental Protection Department. Retrieved25 January 2017.
Pomeranz, Kenneth; Topik, Steven (1999).The World that Trade Created: Society, Culture, and World Economy, 1400 to the Present. Armonk,NY: M.E. Sharpe.ISBN978-0-7656-0250-3.
Puffert, Douglas J (2009).Tracks across Continents, Paths through History: The Economic Dynamics of Standardization in Railway Gauge. University of Chicago Press.ISBN978-0-226-68509-0.
"Standard Railway Gauge".Townsville Bulletin. 5 October 1937. p. 12. Retrieved19 March 2014 – via National Library of Australia., a discussion of the Roman gauge origin theory.