Badische Hauptbahn
The state railway of the French occupation zone in 1945 decided to continue the operation of the 20 kV 50 Hz experiment on the Höllentalbahn, which had operated on the line between 1936 and 1944. Electrification on the Baden Mainline at 15 kV 16 2/3 Hz, started in 1952, was completed to Freiburg by the end of May 1955. As the locomotives could not operate at 50 Hz, steam locomotives hauled freight trains from the Freiburg freight yard via the Hauptbahnhof to the Höllentalbahn. This system ran for five years before the experiment on the Höllentalbahn was abandoned. The two-system operation also made the establishment of ab eighth platform track necessary. With the electrification of the main line from Basel, a class E 10 electric locomotives hauled the first service to Freiburg on 4 June 1955, a day later it was hauled by a class 38 steam locomotive to Stuttgart.