What is a Narrow Span Rail Line? Narrow-span railway is a Railway with a rail track span less than 1,435mm. Most narrow span railways have a span of 600 to 1,067 mm.
Because narrow span railways are generally constructed with smaller radius curves, smaller construction gauge and lighter rails, they are less costly than standard or wide span railways, especially in mountainous or difficult terrain. It is generally used in areas such as industry and mining. Narrow-span railways are common in North America, Switzerland, the former Yugoslavia and Greece.