This article has been partially translated from the German wikipedia article. S-Bahn refers to suburban
metro railways in
Austria,
Germany and
Switzerland. The name is an abbreviation for the German "Stadtschnellbahn" (fast city train) and was introduced in December 1930 in
Berlin, after "SS-Bahn" (Stadtschnell...) had been unofficially in use already. The S-Bahn is a railway that serves metropolitan traffic as well as direct regional traffic, and is characterised by high efficiency and a synchronised timetable that allows for denser train traffic on the rail lines. This is achieved by the use of separate tracks, electric
locomotives and train doors at platform level (in some cities these standards are not met though). The symbol for the S-Bahn in Germany is a white "S" on a green circle.
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