The West Holstein Railway Company was founded in 1875 with the aim of connecting the west Holstein region in the present-day district of Dithmarschen in the German state of Schleswig-Holstein with the railway junction of Neumünster and beyond with the cities of Kiel and Lübeck.
From here, the town of Tönning on the Eiderstedt peninsula was reached by means of a steam ferry, which operated from 6 August 1878.
The bridging of the river would have been too expensive because of its considerable width and only in 1886 was the Marsh Railway extended through Friedrichstadt.
This extension made the line to Karolinenkoog largely unnecessary, so that the northern section was closed in 1942 after a long period of low use.
Today Nordbahn Eisenbahngesellschaft operates passenger services from Neumünster via Heide to Büsum.