Mountain railwayA Mountain railway is a railway which ascends and descends a mountain slope that has a steep grade. There are funiculars that use a winch and cables to haul a cable car or waggons up and down a generally straight track. And there are centre traction rail systems that may use a rack and pinion system or a friction wheel system that allows the railway locomotives to haul themselves up the rail. Mountain railways commonly have a narrow gauge to allow for tight curves in the track and reduce tunnel size and hence construction cost and effort.
Without a mountain railway system, on steep grades, gravity can apply sufficient translating force on the locomotives' wheels to overcome the friction between the wheels and the rails, and the locomotive will simply slide down the track. Ordinarily, railway locomotives require grades no steeper than 1 in 40 for practical operations. While ordinary railway locomotives can operate on grades as steep as 1 in 30, their hauling capacity is limited and more powerful locomotives are normally required. Traction rail systems can easily operate on grades as steep as 1 in 12, a grade that challenges all but the lightest locomotives or railcars.
On very steep grades cables are used because they are stronger than the normal railway couplings between the railway cars. The car itself is often custom built for the slope, with specially raked seatin and steps rather than a sloped floor. Taken to its logical conclusion as the slope becomes vertical, a funicular becomes an elevator (British English: lift).
Mountain Railways in England
Mountain Railways in Scotland
Mountain Railways in Wales
Mountain Railways on the Isle of Man
Mountain Railways in Germany
Mountain Railways in Switzerland
Historic Mountain Railways in New Zealand