Badische Hauptbahn
The Baden main line () is a German railway line that was built between 1840 and 1863. It runs through Baden, from Mannheim via Heidelberg, Karlsruhe, Offenburg, Freiburg, Basle, Waldshut, Schaffhausen and Singen to Constance ("Konstanz"). The Baden Mainline is 412.7 kilometres long, making it the longest route in the Deutsche Bahn network and also the oldest in southwest Germany. The section between Mannheim and Basle is the most important northern approach to the Swiss Alpine passes, whilst the section between Basle and Constance is only of regional significance. The stretch from Karlsruhe to Basle is also known as the Rhine Valley Railway ("Rheintalbahn") and the Basle–Constance section as the High Rhine Railway ("Hochrheinstrecke").