Lorettoberg and the one beneath the Sternwald. The eastern border fault of the Upper Rhine Plain goes through the Lorettoberg. It can be seen through a ‘window’, which has been left open whilst bricking the tunnel so the further subsidence can be measured. In the course of the construction works, the line from the central station to Wiehre was increased to two tracks. The former train station Alter Wiehre Bahnhof (Old Wiehre Station) is now used for cultural activities, for example as a building for film and literature with the ‘Kommunales Kino Freiburg’ (municipal cinema Freiburg), the 'Literaturbüro Freiburg' (lit.: literature office Freiburg) and it also houses a café. Route After leaving Freiburg Hauptbahnhof, the main station for the city of Freiburg, the Höllentalbahn diverges from the mainline Mannheim–Karlsruhe–Basel railway to the east. It the crosses over the mainline on a flyover and serves two further stops within the city, before starting its ascent of the Höllental. High points on the stretch of the line through the Höllental include the Hirschsprungfelsen (a rock formation) and a crossing of the Ravenna Gorge on the high Ravenna Bridge. The section of the line between Hirschsprung and Hinterzarten has a steep maximum gradient of 5.5%, betraying its origin as a rack railway. After leaving the Höllental, the Dreiseenbahn railway to Seebrugg diverges at the spa town of Titisee, close to the Titisee lake. The town of Neustadt follows; since the electrification of the section to Donaueschingen in 2019, passengers do not have to change trains there anymore. Further on, between Neustadt and Donaueschingen, the viaduct at the former crosses the Wutach at the beginning of its long gorge. While in a tunnel near Döggingen station, the line crosses a main European watershed, between the Rhine drainage basin (flowing into the North Sea) and the Danube drainage basin (flowing into the Black Sea). Construction engineering The Höllentalbahn has 15 tunnels on its railway section. Nine of them are on the section between Freiburg and Neustadt (front section) and six of them are on the section between Neustadt and Donaueschingen (back section). The longest tunnel is the Dögginger Tunnel with a length of 535 metres. It passes beneath the European watershed between the Black Sea and the North Sea. All the tunnels on the back section between Neustadt and Donaueschingen were built with the building of the railway section; in contrast to the front section