5 ft and 1520 mm gauge railways

Railways with a railway track gauge of 5 ft/​1,524 mm 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 Russian Railways to be 1520 mm (4 ft 11 ⁄₃₂ in).