Lower-cost narrow-gauge railways are often built to serve industries as well as sparsely populated communities where the traffic potential would not justify the cost of a standard- or broad-gauge line.
[3] The world's first steam locomotive, built in 1802 by Richard Trevithick for the Coalbrookdale Company, ran on a 3 ft (914 mm) plateway.
The first commercially successful steam locomotive was Matthew Murray's Salamanca built in 1812 for the 4 ft 1 in (1,245 mm) Middleton Railway in Leeds.
In 1842, the first narrow-gauge steam locomotive outside the UK was built for the 1,100 mm (3 ft 7+5⁄16 in)-gauge Antwerp-Ghent Railway in Belgium.
Common uses for these industrial narrow-gauge railways included mining, logging, construction, tunnelling, quarrying, and conveying agricultural products.
F. C. Blake built a 7 hp petrol locomotive for the Richmond Main Sewerage Board sewage plant at Mortlake.
[9] Extensive narrow-gauge rail systems served the front-line trenches of both sides in World War I.
[10][11] They were a short-lived military application, and after the war the surplus equipment created a small boom in European narrow-gauge railway building.
[12] In Japan and Queensland, recent permanent-way improvements have allowed trains on 3 ft 6 in (1,067 mm) gauge tracks to exceed 160 km/h (99 mph).
[13] The speed record for 3 ft 6 in (1,067 mm) narrow-gauge rail is 245 km/h (152 mph), set in South Africa in 1978.
[14][15][16] A special 2 ft (610 mm) gauge railcar was built for the Otavi Mining and Railway Company with a design speed of 137 km/h (85 mph).
1,067 mm (3 ft 6 in) between the inside of the rail heads, its name and classification vary worldwide and it has about 112,000 kilometres (70,000 mi) of track.
There were a number of large 3 ft (914 mm) railroad systems in North America; notable examples include the Denver & Rio Grande and Rio Grande Southern in Colorado; the Texas and St. Louis Railway in Texas, Arkansas and Missouri; and, the South Pacific Coast, White Pass and Yukon Route and West Side Lumber Co of California.
Several 18 in (457 mm) gauge railways were built in Britain to serve ammunition depots and other military facilities, particularly during World War I.