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While railways have a great ability to haul very heavy loads, this advantage only really applies when the tracks are fairly level. As soon as the gradients stiffen, the tonnage that can be hauled is greatly diminished.

Contents 1 Techniques to overcome steep hills 2 History 3 Ruling gradient 4 Examples 4.1 Liverpool and Manchester Railway 4.2 Cromford and High Peak Peak Railway 4.3 Redruth and Chasewater Railway 4.4 Lancaster and Carlisle Railway 5 See also

Some of the techniques that can be used to overcome steep hills include:

• dividing the load or splitting the train.
• attaching additional banking engine(s).
• replacing the engine with a more powerful heavier engine for the duration of the steep grade.
• using two-in-one articulated locomotives such as the Fairlie, Garratt or Mallet locomotive.
• using a Booster engine
• Zig Zags
• Spirals
• Horseshoe curves
• Rack railway
• Fell mountain railway system
• Elevators, cable railways, or funicular railways driven by stationary engines (cable haulage up and down inclines).
• Geared steam locomotives such as a Shay locomotive
• Atmospheric railway
• Cable car (railway)

Early tramways and railways were laid out with very gentle grades because locomotive and horse haulage were so low in tractive effort. The only exception would be with a line that was downhill all the way for loaded traffic. Brakes were very primitive at this early stage.

Where a railway has to cross a range of mountains, it is important to lower the summit as much as possible, as this reduces the steepness of the gradients on either side. This can be done with a summit tunnel or a deep summit cutting.

A summit tunnel can lower the summit even more, and paradoxically, the steeper the hill, the shorter the tunnel tends to be; tunnels cost the same no matter how much overburden there is, while cuttings tend to increase in cost with the square of the overburden.

Care had to be taken with summit tunnels in the early days of steam with designs that suffered from problems with smoke and slippery rail. Notorious tunnels came to be known as rathole tunnels.

The ruling gradient of a section of railway line between two major stations is the gradient of the steepest stretch. The ruling gradient governs the tonnage of the load that the locomotive can haul reliably.

The pioneering Liverpool and Manchester Railway was built at a time when choice between locomotive and cable haulable was not clear cut. Therefore all hill climbing (1 in 100) sections was concentrated in one place where cable haulage by stationary engines could be used if necessary, while the rest of the line was engineered to be so gently graded (say 1 in 2000) that even primitive locomotives would have a chance of succeeding. As it turned out at the Rainhill Trials of 1829, locomotives proved capable of handling the short 1.6-km length of 1 in 100 gradients on either side of the Rainhill level.

Since the early trains had primitive brakes, it was also necessary to have very gentle gradients to reduce the need for strong brakes. Sudden changes in gradients would have also overstressed the primitive couplings between the carriages.

The gentle 1 in 2000 gradients were made possible by very substantial earthworks and bridges.

The Cromford and High Peak Railway also opened in 1830 but had gradients so steep - 1 in 8 - that cable haulage was essential. It hauled mainly coal. [1]

The Redruth and Chasewater Railway, a narrow gauge route across the Cornish peninsula (planned in 1818, opened in 1825) used a significant incline to access the harbour at Portreath, which like many in Cornwall sits in a steep valley.

On the Lancaster and Carlisle Railway (L&CR) of 1847 a deep cutting was cut at the Shap Summit. This cutting was cut through rock, about 0.5 mile (800 m) in length, and is between 50-60 feet (15-20 m) deep.

• Funicular railway
• Lickey Incline
• Mountain railway
• Rack railway
• Ruling gradient
• Slope

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Running lines	Single track • Passing loop • Double track
Rail sidings	Balloon loop • Headshunt • Rail yard • Classification yard
Junctions	Flying junction • Level junction • Double junction • Facing and trailing • Grand union • Wye • Railroad switch
Stations	Side platform • Island platform • Bay platform • Terminal station • Balloon loop • Spanish solution • Cross-platform interchange
Hillclimbing	Horseshoe curve • Zig Zag / Switchback • Spiral