Standard-gauge railway

 ( Track Gauges By Size ) 

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 main wheel flanges that fit inside the rails is better, thus the minimum distance between the wheels (and, by extension, the inside faces of the rail profile) 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 than . Wylam colliery's system, built before 1763, was , as was John Blenkinsop's Middleton Railway; the old plateway was relaid to so that Blenkinsop's engine could be used. Others were (in Beamish) or (in Bigges Main (in Wallsend), Kenton, and Coxlodge).

English railway pioneer George Stephenson spent much of his early engineering career working for the coal mines of County Durham. He favoured

() for wagonways in [[Northumberland]] and Durham, and used it on his [[Killingworth]] line. The [[Hetton|Hetton-le-Hole]] 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. Opening in 1825, the initial gauge of was set to accommodate the existing gauge of hundreds of horse-drawn Chaldron that were already in use on the in the mines. The railway used this gauge for 15 years before a Gauge conversion was made, debuting around 1850, to the gauge. 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 gauge since its inauguration in 1868.

George Stephenson introduced the gauge (including a belated extra of free movement to reduce binding on curves) for the Liverpool 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.

The success of this project led to Stephenson and his son Robert being employed to engineer several other larger railway projects. Thus the 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 than . "I would take a few inches more, but a very few"..

During the "Gauge War" with the Great Western Railway, standard gauge was called "narrow gauge", in contrast to the Great Western's 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.

After an intervening period of dual gauge operation (tracks were laid with three rails), the Great Western Railway finally completed the Gauge conversion of its network to standard gauge in 1892. In North East England, some early lines in colliery (coal mining) areas were , while in Scotland some early lines were . 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 broad gauge track in the South was converted to "almost standard" gauge over the course of two days beginning on 31 May 1886. See Track gauge in the United States.

In continental Europe, France and Belgium adopted a gauge (measured between the midpoints of each Rail profile) for their early railways.Auguste Perdonnet, mémoire sur les chemins à ornières, 1830 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, to in France). The first tracks in Austria and in the Netherlands had other gauges ( in Austria for the Donau Moldau line and 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.Revue générale des chemins de fer, July 1928.

• The Huddersfield Corporation Tramways, used
• The Portsdown and Horndean Light Railway, used
• The Portsmouth Corporation Transport, used
• The Killingworth colliery railway, used ..
• The Hetton colliery railway, opened 1822, used .
• The Stockton and Darlington Railway, authorised 1821, opened 1825, used .
• The New Orleans and Carrollton Railroad used
• The Pontchartrain Railroad used
• The trams in Nuremberg nominally used during much of their existence, but have since been converted to standard gauge in name as well as fact.

• The Manchester and Leeds Railway, authorised on 4 July 1836, used ..
• The railways were intended to take gauge vehicles and allow a (second) running tolerance.
• The Chester and Birkenhead Railway, authorised on 12 July 1837, used ..
• The London and Brighton Railway, authorised on 15 July 1837, used ..
• The Manchester and Birmingham Railway, authorised on 30 June 1837, used ..
• The Pennsylvania Railroad originally used
• The trams in Dresden, authorised in 1872 as , used gauge vehicles. Converted to 600 V DC electric trams in 1893, they now use ; both gauges are within the tolerance for standard gauge.
• The Ohio gauge of

• Cheltenham and Great Western Union Railway, authorised 1836, opened 1840, dual gauge 1843 and .

• South Africa became
• Thailand became
• Indonesia became
• Ireland became – Dublin and Kingstown Railway
• Australia became – Victoria & South Australia – partly converted to
• India became – initial freight lines
• some private railways

• The Toronto Transit Commission uses a Toronto gauge of on its streetcar and heavy-rail Toronto subway lines, which was actually closer to gauge.
• The Toronto Transit Commission Light metro lines and light rail lines (whether existing, under construction or proposed) use standard gauge.
• Trams in Leipzig, Germany use .
• Trams in Dresden, Germany use .
• gauge is in use on several urban rail transit systems in Europe:
• Trams in Italy
• Madrid Metro (only metro system. Metro Ligero uses standard gauge.)
• The MTR in Hong Kong uses gauge on lines owned by the MTR Corporation. However, lines formerly operated (but which continue to be owned) by the Kowloon-Canton Railway Corporation, including the Light Rail network, use gauge. New lines and extensions to the MTR after 2014 use gauge, including the South Island line, Kwun Tong line extension and West Island line.
• The Bucharest Metro uses gauge.
• The Washington Metro uses , narrower than standard gauge.
• The Mount Washington Cog Railway, the world's oldest mountain-climbing Rack railway, uses a gauge.

• Standard Gauge (toy trains)
• List of tram systems by gauge and electrification
• Track gauge
• Railway Regulation (Gauge) Act 1846

• Geoffrey Freeman Allen (1987). 9780710608482, Jane's Information. ISBN 9780710608482
• Bertran Baxter (1966). 9780715340042, David & Charles. ISBN 9780715340042
• Robin Jones (2025). 9781909128279, Mortons Media. ISBN 9781909128279
• Stephen K Jones (2025). 9780752449128, The History Press. ISBN 9780752449128
• (1999). 9780765602503, M.E. Sharpe. ISBN 9780765602503
• Douglas J Puffert (2025). 9780226685090, University of Chicago Press. ISBN 9780226685090
• João Bosco Setti (2025). 9788586094095, Memória do Trem. . ISBN 9788586094095
• A. Vaughan (1997). 9780719551505, John Murray. . ISBN 9780719551505
• Francis Whishaw (1969). 9780715347867, David & Charles; reprints: Newton Abbot. ISBN 9780715347867

• , a discussion of gauge in Australia
• , a discussion of the Roman gauge origin theory.