Badische Hauptbahn
The Karlsruhe—Heidelberg section of the Rhine Valley Railway was opened on 15 April 1843 as part of the construction of the Baden Mainline from Mannheim via Heidelberg, Karlsruhe, Baden-Baden and Freiburg to Basel, which was initially built to 1600 mm broad gauge. As a result, Walldorf and Wiesloch gained a connection to the rail network. A few years later the line was duplicated. Since the Grand Duchy of Baden State Railway’s broad gauge was not compatible with the gauge of neighbouring countries, it now feared the loss of lucrative transit traffic. Therefore, in 1854, Baden began to regauge its lines to and this was completed in just four months from Mannheim to Bruchsal.