The Brienz Rothorn Bahn is the only one of Switzerland’s many mountain railways that is usually operated by steam locomotives. It extends for 7.6 km from the town of Brienz, where there are connections with trains on the Brünig line linking Lucerne and Interlaken, and with steamers on Lake Brienz to a station near the summit of the mountain, 2244 m above sea level, which includes a restaurant. The 80 mm gauge line operates according to the rack system devised by the Swiss engineer Roman Abt (1850-1933), in which one tooth of the rack wheel is always engaged with the track. Some 72 railways in the world were equipped with the system. The line opened in 1892 but was closed between the outbreak of the First World War and 1931. The oldest locomotives used on the railway date from the time of its opening.