The summer timetable of 1956 included three six-part reversible train sets deployed by the Dortmund central station railway depot (Bw Dortmund Hbf). Comprising a Bif (control car), an ABib and four Bib cars of standard design, these sets were pulled or pushed, depending on the direction, by a 78-series locomotive stationed at Bw Dortmund Hbf. In the precursor to the S-Bahn service, these reversible trains departed Dortmund central station multiple times daily, heading to Hagen, Witten, Herne, Wanne-Eickel and Gelsenkirchen. The three timetables commenced between 4 and 5 am and, in some cases, ran until shortly before midnight. With a typical turnaround time of about ten minutes at the destination station, the advantages of these reversible trains were fully exploited in terms of the timetable.