Rhine-Ruhr Stadtbahn

Rhine-Ruhr Stadtbahn (German: Rhein-Ruhr Stadtbahn) is an umbrella system of all of the Stadtbahn (light rail) lines included in the integrated public transport network of Verkehrsverbund Rhein-Ruhr (VRR) which covers the Rhine-Ruhr metropolitan area in western Germany. It does not include the independent Cologne Stadtbahn and Bonn Stadtbahn systems.

At the beginning of the 1960s, road traffic in the Rhine-Ruhr area increased like in other German metropolitan areas. Existing trams were regarded as obstacles for car-oriented cities. Therefore, these trams should be relocated to underground sections below city centers (as Stadtbahn lines) if they were not replaced by bus lines.

The cities of Bochum, Castrop-Rauxel, Dortmund, Duisburg, Essen, Gelsenkirchen, Herne, Mülheim an der Ruhr, Oberhausen, Recklinghausen and Wattenscheid founded the Stadtbahngesellschaft Ruhr in 1969 for coordinating the plans to transform tram routes into Stadtbahn routes. Düsseldorf and Hattingen joined in 1972; since then, the cooperation has been called Stadtbahngesellschaft Rhein-Ruhr. Witten joined in 1981, Recklinghausen left in 1982.

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