 The route of a section of the line is now used by part of federal highway 5 running between the end of Autobahn 23 at Heide-West via Hemme to the Eider bridge at Tönning.The Heide–Karolinenkoog railway was opened, together with the Neumünster–Heide railway, on 22 August 1877.It was built and operated by the West Holstein Railway Company ("Westholsteinische Eisenbahn-Gesellschaft").