Railways with a railway track gauge of were first constructed in the United Kingdom and the United States. This gauge is also commonly called Russian gauge because this gauge was later chosen as the common track gauge for the Russian Empire and its neighbouring countries. The gauge was redefined by Soviet Railways to be 1,520 mm .
The primary region where Russian gauge is used is the former Soviet Union (CIS states, Baltic states, Georgia and Ukraine), Mongolia and Finland, with about 225,000 km (140,000 mi) of track. Russian gauge is the second most common gauge in the world, after .
In 1748, the Wylam waggonway was built to a gauge for the shipment of coal from Wylam to Lemington down the River Tyne. In 1839, the Eastern Counties Railway was constructed; and in 1840, the Northern and Eastern Railway was built. In 1844, both lines were converted to . In 1903, the East Hill Cliff Railway, a funicular, was opened.
In 1827, Horatio Allen, the chief engineer of the South Carolina Canal and Rail Road Company, prescribed the usage of gauge and many other railroads in Southern United States adopted this gauge. The presence of several distinct gauges was a major disadvantage to the Confederate States of America during the American Civil War. In 1886, when around 11,500 miles (18,500 km) of gauge track existed in the United States, almost all of the railroads using that gauge were converted to , the gauge then used by the Pennsylvania Railroad.
The first railway built in Russia was built in 1837 to gauge for a 17 km long "experimental" line connecting the Imperial Palaces at Tsarskoye Selo and Pavlovsk; the choice of gauge was influenced by Brunel's Great Western Railway which used . While of almost no practical importance the railway did demonstrate that this gauge was viable. The second railway in the Russian Empire was the Warsaw-Vienna railway (Congress Poland was then a part of the Empire) which was built to and commenced construction in 1840.
For the building of Russia's first major railway, the Moscow - Saint Petersburg Railway, engineer Pavel Melnikov hired as consultant George Washington Whistler, a prominent American railway engineer. Whistler recommended on the basis that it was cheaper to construct than while still offering the same advantages over and that there was no need to worry about a break-of-gauge since it would never be connected to the Western European railways. Colonel P.P. Melnikov, of the Construction Commission overseeing the railway, recommended following the example of the first railway and his study of US Railways. Following a report sent by Whistler the head of the Main Administration of Transport and Buildings recommended and it was approved for the railway by Tsar Nicholas I on February 14, 1843. The next lines built were also approved with this gauge but it was not until March 1860 that a Government decree stated all major railways in Russia would be gauge.
It is widely and incorrectly believed that Imperial Russia chose a gauge broader than standard gauge for military reasons, namely to prevent potential invaders from using the rail system. In 1841 a Russian army engineer wrote a paper stating that such a danger did not exist since railways could be made dysfunctional by retreating or diverting forces. Also the construction of the Warsaw-Vienna railway in was precisely so it could be connected to the Western European network, in that case to reduce Poland's dependence on Prussia for transport. Finally for the Moscow - Saint Petersburg Railway, which became the benchmark, the choice of track gauge was between and the wider , not standard gauge . However, it was just not selected with that in mind. When a railway has wooden sleepers, it is fairly easy to make the gauge narrower by removing the nails and placing them back at a narrower position, something Germany did during WWII. Destroying river bridges had a larger effect.
The 5-foot gauge became the standard in the whole Russian Empire, and its successor Soviet Union and Finland and in the once Soviet-influenced Mongolia. That area is now the Baltic states, Ukraine, the CIS states, which include Russia, Belarus and the Caucasian and Central Asian republics, .
Russian engineers used it also on the Chinese Eastern Railway, built in the closing years of the 19th century across the Northeastern China entry to provide a shortcut for the Transsiberian Railway to Vladivostok. The railway's southern branch, from Harbin via Changchun to Lüshun, used the Russian gauge, but as a result of the Russo-Japanese War of 1904-1905 its southernmost section (from Changchun to Lüshun) was lost to the Japanese, who promptly regauged it to standard gauge (after using the narrow for a short time during the war). This formed a break of gauge between Changchun and Kuancheng (the station just to the north of Changchun, still in Russian hands), until the rest of the former Chinese Eastern Railway was converted to standard gauge, too (probably in the 1930s).
Unlike in South Manchuria, the Soviet Union's reconquest of southern Sakhalin from Japan did not result in regauging of the railway system. Southern Sakhalin has continued with the original Japanese gauge simultaneously with the Russian gauge railway, constructed in the northern part of the island in 1930-1932 (Moskalvo-Okha). The railway has no fixed connection with the mainland, and rail cars coming from the mainland port of Vanino on the Vanino-Kholmsk train ferry (operating since 1973) have their bogies changed in the Sakhalin port of Kholmsk. In 2004 and 2008 plans were put forward to convert it to Russian gauge. The estimated completion date now is 2030.
There were proposals in 2013 for north-south and east-west lines in Afghanistan, with construction to commence in 2013.
The Panama Railway, first constructed in ca. 1850, was built in gauge. During canal construction (1904–1914), this same gauge was chosen for both construction traffic, canal operating services along the quays, and the newly routed commercial cross-isthmus railway. In 2000 the gauge for the commercial parallel railway was changed to to use standard gauge equipment. The original gauge was chosen under the influence of the pre-conversion southern United States railway companies. Nowadays, the electric manoeuvering locomotives along the locks (mules) still use the gauge that was laid during canal construction.
The first rail line in Finland was opened on January 31, 1862. As Finland was then the Grand Duchy of Finland; a region of Imperial Russia, railways were built to the then Russian track gauge of , although the railway systems were not connected until the bridge over River Neva was built in 1913. Russian trains could not have run in the Finnish tracks, because the Finnish loading gauge was narrower until the connection was made, and the Finnish structure gauge was widened.
In the late 1960s the gauge was redefined to in the Soviet Union. At the same time the tolerances were tightened. As the running gear (wheelsets) of the rolling stock remained unaltered, the result was an increased speed and stability. The conversion took place between 1970 and the beginning of the 1990s.
In Finland Finnish State Railways kept the original definition of , even though they also have tightened the tolerances in a similar way. (Tolerance tighter than in the Soviet Union)
Estonia after independence redefined its track gauge to to match Finland's. The redefinitions did not mean that a lot of railways were changed. It was more a rule change regarding new and renovated tracks. See: Track gauge in Estonia.
Finland allows its gauge to be 1,514-1,554 mm (less tolerance for higher speed).
If the gauge of the rolling stock is kept with certain limits, through running between railways and Finnish railways is allowed. Since both 1,520 and 1,524 mm are well within tolerances, the difference can be said to be mostly a paper difference. However, certain Finnish rolling stock do have a tendency to get stuck in Russian railyards due to too narrow gauge.
The international high-speed train Allegro (Sm6) between Helsinki and St. Petersburg is specified as 1,522 mm gauge. High-speed trains have less tolerance against gauge error, but this way through running works well.
The loading gauge, that is permitted height and width of trains, is larger for Russian gauge. This means that if a standard gauge railway shall be adapted for dual gauge, bridges must be rebuilt, double tracks must be placed further apart and the overhead wire must be raised. Or there must be restrictions on permitted rolling stock, which would restrict the benefit of such a railway. Dual gauge needs more width than single gauge.
There is an approximately 150 km long section in Hungary in the Záhony logistics area close to the Ukrainian border. During the recent renovation a 32 km section of dual Standard/Russian gauge was installed between Tumangang and Rajin stations in the DPRK.
Although broad gauge is quite rare on lighter railways and street tramways worldwide, almost all tramways in ex-USSR are broad gauge (according to terminology in use in these countries, gauges narrower than are considered to be narrow). Many tramway networks initially built to narrow gauges ( or ) were converted to broad gauge. As of 2015, only a few out of more than sixty tram systems in Russia are not broad gauge: in Kaliningrad and Pyatigorsk, in Rostov-on-Don; there are also two tram systems in and around Yevpatoria that use gauge. The Helsinki trams and Liep?ja trams also use , and the Tallinn trams use .
These gauges cannot make 3-rail dual gauge with Russian gauge.
That is .
|China||China Eastern Railway (until 1930s); Rail North China (proposed)|
|Finland||Rail transport in Finland|
|Former Soviet Union||Prior to narrowing the gauge on the paper by 4 mm to and narrowing the tolerances; the railways adjusted only when needed or upgraded.|
|Japan||Sakhalin-Hokkaido tunnel (proposed), with the break-of-gauge facilities between and in Northern Hokkaido.|
|Norway||Proposed for Kolari-Skibotn-Tromsø and Pechenga/Nikel-Kirkenes-Lakselv-Skibotn lines.|
|Panama||Panama Railway prior to conversion to standard gauge in 2000 to suit off-the-shelf supply.|
|Sweden||Only a small freight yard in Haparanda. Used for exchanging cargo with Finnish trains; Proposed for the Vaasa-Umeå-Luleå-Haparanda-Tornio Line which will parallel with North Bothnia Line and Haparanda Line between Umeå and Haparanda.|
|United States||The South, such as the Cartersville and Van Wert Railroad, the Cherokee Railroad, and the Western & Atlantic Railroad, until May 31, 1886. The Duquesne Incline and Monongahela Incline in Pittsburgh, Pennsylvania.|
That is .
|Afghanistan||Rail transport in Afghanistan: The northern spur lines from CIS states. For Afghanistan's future network, standard gauge for the western spur lines from Iran, and Indian gauge are proposed.|
|Armenia||Armenian Railways, South Caucasus Railway|
|Austria||Ko?ice-Vienna broad-gauge line (proposed)|
|Belarus||Rail transport in Belarus|
|Bulgaria||Only at Varna ferry terminal for train ferries to Odessa and Poti; dual gauge track for changing wagon bogies with standard gauge ones, and parallel transhipping tracks of and gauge.|
|China||Several short stretches from Russia, Mongolia and Kazakhstan.|
|Estonia||Rail transport in Estonia|
|Germany||Only at Sassnitz/Mukran ferry terminal for freight train ferries to Turku, Klaip?da and Baltijsk.|
The gauge is proposed for 2 new lines, one from Brest (Belarus) through Warsaw to Berlin, the other from Kaliningrad through Baltic coast to Hamburg.
|Hong Kong||Peak Tram|
|Kazakhstan||Kazakhstan Temir Zholy|
|Latvia||Rail transport in Latvia|
|Mongolia||Rail transport in Mongolia|
|North Korea||A 32-km stretch of 1,435/ dual gauge between Tumangang and Rajin Stations.|
|Poland||Almost exclusively on the Broad Gauge Metallurgy Line.|
|Slovakia||Only on the "?irokorozchodná tra?" (Uzhhorod - Ma?ovce - Haniska pri Ko?iciach) and from the border station of Dobrá pri ?iernej nad Tisou to Ukraine, both operated by ZSSK Cargo.|
|Tajikistan||Rail transport in Tajikistan: Most in the West; Also Indian gauge is proposed for the East.|
|Turkmenistan||Railways in Turkmenistan|
The nominal track gauge on the rail network 1,524 mm. The tolerance range is -10...+30 mm