The Dortmund Stadtbahn is a light rail system in the German city of Dortmund and is integrated in the Rhine-Ruhr Stadtbahn network.

Its network consists of eight lines and is operated by Dortmunder Stadtwerke, which is operating under the brand DSW21 since 2005.

The light rail system was gradually opened between 1976 and 2008 by relocating the inner-city tram tracks in underground tunnels and opening new express tram routes that are independent of road traffic (e.g. Kirchderne – Grevel).

It operates on 75.0 kilometres (46.6 mi) of route (of which 20.5 kilometres (12.7 mi) are underground in tunnels, with the other 54.5 kilometres (33.9 mi) being above-ground in dedicated rights-of-way).

[1] The system has eight Stadtbahn lines:[3] The U41 and U47 rail lines connect with bus 490, which travels to Dortmund Airport.