Stadtbahn

A Stadtbahn (German pronunciation: [ˈʃtatˌbaːn]; German for "city railway"; plural Stadtbahnen) is a tramway or light railway that includes segments built to rapid transit standards, usually as part of a process of conversion to a metro railway, mainly by the building of metro-grade tunnels in the central city area.

Stadtbahn networks were mostly implemented in the 1960s and 1970s with the long-term goal of establishing a full-scale metro system, but by the 1980s virtually all cities had abandoned these plans due to the excessive costs associated with converting the tramways. Most Stadtbahn systems are now a mixture of tramway-like operations in suburban and peripheral areas and a more metro-like mode of operation in city centres, with underground stations. This Stadtbahn concept eventually spread from Germany to other European countries, where it became known as pre-metro.

The term Stadtbahn first arose in the first half of the 20th century as a name for the cross-city lines in Berlin and Vienna. The Berlin Stadtbahn line is an elevated heavy rail line linking the East and the West. Long distance, regional, suburban, and urban services (S-Bahn) are operated on it.

The Wiener Stadtbahn (Vienna) was in the beginning a system of heavy rail lines circling the city, free of level crossings, operated by steam trains. After World War I the Wiental, Donaukanal and Gürtel lines were converted into an electric light rail system with tram-like two-axle cars (which on line 18G until 1945 switched into the tram network at Gumpendorfer Strasse station). In the 1970s to 1990s the infrastructure was updated, and the lines were partially relocated: they are now part of the Vienna U-Bahn services 'U4' and 'U6'. The Vorortelinie line remained heavy rail and is now part of the Vienna S-Bahn.

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