Montaña Suiza (“The Swiss Mountain” in English) is a steel scenic railway roller coaster located at Monte Igueldo Amusement Park, on the coast at San Sebastián, Spain. It was designed and built by German engineer Erich Heidrich and opened at the site in 1928. It is the oldest steel roller coaster still operating in the world.

The ride was built with wooden running rails in a trough, like usual scenic railways. The trough is partially set into the landscape and is of concrete construction. The ride lacks the traditional supporting trestles of scenic railways. Instead, the track runs in depressions set into the ground and along the top of a coastal wall at one point. The running rails were changed to steel at a later unknown date.

The roller coaster operates with two trains, each of which is composed of two 2×5-person cars. The cars are wooden in construction and ride on steel bogies, like the scenic railways at Margate, UK, Great Yarmouth Pleasure Beach, UK, and Luna Park, Melbourne. A brakeman rides on board each train to control its speed.

Montaña Suiza is 400m-long, 10m-high and can reach 50km/h.

According to the Wikipedia