The Marsh Railway () is a main line in the state of Schleswig-Holstein in Germany that links the stations of Elmshorn in the south and Westerland on the island of Sylt in the north. It is part of long route from Hamburg-Altona to Westerland (Sylt) and is listed in the Deutsche Bahn timetables as . The first part of it was opened in 1845 and is one of the oldest lines in Germany. Route The Marsh Railway, as its name suggests, mainly runs through marshlands. There are also some sections of the line that run through the higher-lying geest. The line branches off the Hamburg-Altona-Kiel railway line in Elmshorn. From Elmshorn, it runs in an arc via Glückstadt to Itzehoe. The line then crosses the Kiel Canal on the high Hochdonn High Bridge. The bridge's total length is and its main span over the channel is long. There is also a bascule bridge north of Husum station. Between Klanxbüll and Morsum stations the line runs across the Hindenburgdamm (causeway) through the North Frisian mudflats. History The first section of the current Marsh Railway was built by the Glückstadt-Elmshorn Railway Company (Glückstadt-Elmshorner Eisenbahn-Gesellschaft) shortly after the opening of the Altona–Kiel line on 18 September 1844. The company opened a line from Elmshorn to Glückstadt port station on 20 July 1845. Twelve years later, on 15 October 1857, the line was realigned in Glückstadt and extended to the edge of the Stör river in Itzehoe. In 1878, a swing bridge was built across the Stör—which was replaced in 1910 during the duplication of the line by two bascule bridges—and the line was extended to the Heide station of the Neumünster–Heide–Karolinenkoog line, which opened on 22 August 1877. On 1 January 1879 the Glückstadt-Elmshorn Railway Company became the Holstein Marsh Railway Company (Holsteinische Marschbahn-Gesellschaft). In 1888, this company was acquired by the Schleswig-Holstein Marsh Railway Company (Schleswig-Holsteinische Marschbahn-Gesellschaft). On 1 July 1890, the company was acquired by the Prussian government and it became part of the Prussian State Railways. In 1886 construction began on an extension and on 1 September 1886 the line was opened via Lunden and a bridge over the Eider near Friedrichstadt to Husum, where it connected with the Flensburg–Husum–Tönning line. The line was extended further north to Bredstedt on 17 October 1887 and to Niebüll on 15 November 1887. The line was subsequently extended further north to Tønder, connecting