S1 (Rhine-Ruhr S-Bahn) Services ran via Düsseldorf Airport Terminal station from 24 May 1998 to 28 May 2000. Services were extended from Düsseldorf to Solingen on 13 December 2009, replacing part of the former line S 7 service. S1 (Rhine-Ruhr S-Bahn) Line S1 is a S-Bahn line on the Rhine-Ruhr network. It is operated by DB Regio. It runs from Dortmund west over Essen to Duisburg. From there it travels south to Düsseldorf and Hilden before continuing to Solingen. It is operated at 20 minute intervals, using coupled sets of class 422 four-car electrical multiple units. Line S 1 runs over lines built
S13 (Rhine-Ruhr S-Bahn) to Troisdorf by the Rhenish Railway in 1870, with an extension to Cologne opened in 1874) and the Cologne Airport loop (opened in 2004) The western section of the S 13 service from Düren to Köln Messe/Deutz was opened on 15 December 2002. It was extended to Troisdorf on 13 June 2004. It is proposed to extend the line to Bonn-Oberkassel. S13 (Rhine-Ruhr S-Bahn) Line S 13 is a S-Bahn line of the Rhine-Ruhr network. It is operated by DB Regio with class 423 electric multiple units. At peak times, the S13 services begin or end at Düren and run