The Witten/Dortmund, Oberhausen/Duisburg railway is one of the most important railways in Germany. It is the main axis of long distance and regional rail transport on the east–west axis of the Ruhr and is served by Intercity-Express, InterCity, Regional-Express, Regionalbahn and S-Bahn trains.
Strictly speaking, the line today consists of two parallel two-track lines, one for mainline trains and the other for S-Bahn trains. On several sections of the line the long-distance tracks and S-Bahn tracks follow separate routes. The long-distance tracks follows the historical route built between 1860 and 1862 by the Bergisch-Märkische Railway Company as an extension of its trunk line between Elberfeld and Dortmund.
History
The Cologne-Minden Railway Company (German, old spelling: Cöln-Mindener Eisenbahn-Gesellschaft, CME) planned the route of its trunk line, built from 1845 to 1847, to avoid the construction costs of a line through the very hilly land along the valleys of the Ruhr and Wupper rivers and in order to minimise operating costs. It was thus cut off from the coal mines, which is the mid-19th Century were found on the north bank of the Ruhr.
Between 1847 and 1849 Bergisch-Märkische Railway Company (Bergisch-Märkische Eisenbahn-Gesellschaft, BME) built its own trunk line in the highly industrialised area in the Wupper valley and the Bergisches Land and decided to extend it to the west through the area between the Ruhr and the Emscher rivers. In particular it wanted to connect the coal mines north of the Ruhr with a port on the Rhine.
Construction of the original line
On 26 October 1860, the first section was opened from Witten BME to Bochum BME (at one time called Bochum Sud station). On 1 March 1862 the section from Bochum to Steele, Essen BME Mülheim BME, Styrum and Oberhausen BME was opened. A few weeks later on 1 May 1862, the section from Styrum to Duisburg BME opened. In the same year, the route from Langendreer BME east to Dortmund BME was rebuilt and opened for passenger traffic on 5 October 1862.
Styrum—Ruhrort line
In later years the line was steadily improved and branches were built. In 1864 the BME took over the management of the lines of the Aachen-Dusseldorf-Ruhrort Railway Company (formally the Königliche Direction der Aachen-Düsseldorf-Ruhrorter Eisenbahn). On 8 January 1866, it took over the company, including the Ruhrort-Homberg train ferry. It opened a line on 4 December 1867 to Ruhrort from Styrum via Meiderich (Sud), partly parallel with the older line of the CME from Oberhausen crossing the Rhine-Herne Canal on a bridge constructed with gauntlet track.
Essen—Bochum—Herne line
On 1 November 1874 the BME opened an additional line parallel to the existing track from Essen BME to Wattenscheid BME and Bochum BME and from there to Riemke, Herne Rottbruch and Herne BME (Bochum–Essen/Oberhausen line). The line was initially used for freight with passenger services commencing on 1 January 1875. After the transfer of the station from the former Bochum BME station to the current Bochum Hauptbahnhof in 1957 the connection from Bochum West to the line to Herne was closed. Instead, a connecting line was built a kilometre east in 1979 from the new Hauptbahnhof to Bochum West.
The route is now divided into two completely different sections. The western section is now used by long-distance services between Duisburg and Dortmund (other services follow the original route), while the northern section is now only used by regional trains to Gelsenkirchen via the Bochum–Gelsenkirchen railway and freight trains.
Redevelopment for the S-Bahn
As part of the establishment of the Rhine-Ruhr S-Bahn in the early 1970s, the line was rebuilt to have at least four-tracks continuously. On 23 September 1973, the four line section between Mülheim and Mülheim-Styrum was inaugurated and on 10 December 1973 it was extended to Duisburg Hbf. After the opening of two more sections on 11 March 1974 between Essen Hbf and Essen-Steele and between Essen Hbf and Essen West, the service between Duisburg Großenbaum Bochum Hbf was designated as S-Bahn line S1 and the service between Oberhausen Hbf and Hattingen designated as S3.
When the Technical University of Dortmund was established in 1968, it was deemed necessary to connect it to the S-Bahn network and on 24 September 1983 a completely new route—partly underground—was opened from Bochum-Langendreer to Dortmund-Dorstfeld, where the line joins the historic route to Dortmund Hauptbahnhof.