Climing to the top of the mountain of the same name, the Mount Washington Railway was the world's first mountain-climbing rack-and-pinion railway. At 4.8km long, an average grade of 25% and a maximum grade of 37.41%, rising from 820m above sea-level to 1,917m at its summit, it is the second-steepest rack railway in the world.
The railway was built by Sylvester Marsh and opened to passengers on 14th August 1868, with the track reaching the summit in July 1869.
During its construction, the railway was noted for its "Devil's Shingles" - slide boards invented by its labourers to fit over the cog rack, with enough room for the worker and his tools, which would then slide down the mountain in around 15 minutes. After the death of an employee, however, the boards were banned.