Düsseldorf Stadtbahn
The Düsseldorf Stadtbahn, together with the Rhine-Ruhr S-Bahn and the Düsseldorf Straßenbahn (Tram), is the backbone of the public transport system of Düsseldorf, Germany, and is integrated in the Rhine-Ruhr Stadtbahn network. The Stadtbahn officially opened on 6 August 1988 and is operated by Rheinbahn AG. , the Stadtbahn network currently consists of eleven lines, operating on , and serving 161 stations, 22 of which are underground stations (Duesseldorf: 16, Duisburg: 6 (U79)). Current lines. U70 is a rush-hour-only "express" line. It operates the same route as the U76, however does not stop at all  stations. The lines U80-U82 are currently in planning and constructions are set to start in late 2020/early 2021. Future expansion. In late 2019 construction work for the new U81 started. The first section will connect the main station (Düsseldorf Hauptbahnhof) and the airport. Opening of this section is scheduled for 2024 and will also enable connections between the arena and the airport. Rolling Stock. There are a total of 135 trainsets for the Düsseldorf Stadtbahn. There are 103 six-axle articulated tramsets (B80), which are operated on the lines U70 and U74-U79 as well as 32 eight -axle articulated tramsets (GT8SU)., which are mostly found on the lines U75 and U77. Both the B80 and the GT8SU have a floor at around 90 cm above the tracks. Furthermore, the lines U71-U73 and U83 are operated by eight-axle trainsets of type NF8U, which have a floor height of 30 cm above the tracks.