Wuppertal City Authority (WSW) placed a €122m order with Vossloh Kiepe and Vossloh Rail Vehicles (now Stadler Rail Valencia) in November 2011 for 31 two-car Generation 15 articulated trains to replace the current fleet of 27 two-car trains, which dates back to 1977.

The trains are being assembled at Stadler Rail Valencia's Albuixech plant near Valencia in Spain, while Vossloh Kiepe is producing electrical equipment for the fleet at its Düsseldorf facility.

Five trains are now in passenger service and the remainder of the fleet is due to enter service by early 2018.

The 13.3km line from Oberbarmen to Wuppertal city centre and Vohwinkel opened in 1901 and carries around 80,000 passengers a day.