Starting in Chamonix, the Montenvers Mountain Railway leads up to Montenvers and the base of the Mer de Glace glacier at 1,913m (6,276ft) above sea level. The glacier is the largest in France, and was arguably the country's first major Alpine tourist attraction, ensuring the demand for - and the continued success of - the line.
The first section of the narrow-gauge railway opened in 1908, and services reached the summit the following year. On the three mile journey to the terminus, the line climbs an impressive 871m (2,858 ft), which it manages with a series of viaducts. Having been electrified in the early 1950s, the railway is worked by both diesel and electric locomotives.