S9 (Rhine-Ruhr S-Bahn)
Line S 9 is an S-Bahn line on the Rhine-Ruhr network, operated by DB Regio. It runs from Haltern am See in the north through Essen to Wuppertal Hauptbahnhof in the south. During the day three services per hour run between Wuppertal and Bottrop Hauptbahnhof, with one service per hour continuing to Haltern, using class 422 electric multiple units.
Line S 9 runs over lines built by various railway companies:
S-Bahn services commenced between Dortmund and Essen on 29 September 1991. Services commenced between Steele Ost and Haltern am See on 24 May 1998. Services were extended to Wuppertal on 14 December 2003.
N9 local service between Kupferdreh and Nierenhof in 1986 prior to the electrification of the Vohwinkel–Überruhr line
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