The Waldenburg railway (; WB) is a narrow-gauge light rail system in the canton of Basel-Landschaft, Switzerland. The long single-track line runs from Liestal, the capital of the canton, to Waldenburg, with stops in Bubendorf, Hölstein, Niederdorf, and Oberdorf. It connects to SBB train services in Liestal railway station. The line was temporarily closed between April 2021 and December 2022 for modernisation and conversion to metre gauge. Since 2016 the line has been operated by Baselland Transport (BLT), and was, with the exception of a few industrial and funicular lines, the only line in Switzerland with a track gauge of . It was opened on 1 November 1880 and was operated by steam-hauled trains until 1953, when electric operation began. New rolling stock was introduced from 1985. On 5 April 2021 the line closed for rebuilding to , and reopened on 11 December 2022. The existing rolling stock has been sold for further service on the Čierny Hron Railway in Slovakia. The system now uses ten seven-car Tramlink vehicles from Stadler Rail. History A concession was granted by the canton of Basel-Landschaft on 18 June 1871 for the construction of a narrow gauge railway from Liestal to Waldenburg and eventually further to Langenbruck. In 1873 the concession was altered to give the Swiss Central Railway the commission to build the railway. For financial reasons in 1876 the Swiss Central Railway requested a deadline extension. On 25 November 1879 the Waldenburgerbahn was founded as a separate company and took over the concession for the railway from Liestal to Waldenburg. After only eight months' construction, the railway opened on 30 October 1880. Seats were provided in second- and third-class carriages. In 1881 the railway served eight stations with four journeys in each direction. The fastest journey over the whole 13 km line took 56 minutes. In 1909 a committee made an application for the construction of and operation of an electric narrow-gauge railway from Waldenburg through Langenbruck to Balsthal, with a connection from St.Wolfgang to Mümliswil. The outbreak of World War I stopped plans for the extension of the line, and a 1912 proposal to electrify the line and regauge it to gauge. On 26 October 1953 electric operation of the railway began, using 1500 V DC. New rolling stock was acquired for this. The current rolling stock, consisting of seven railcars and 10 control cars was acquired between 1986 and 1993,