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
Battle of the Ruhr or the "valley of no Return". During the battle other German targets received large attacks. In his study of the German war economy, Adam Tooze stated that during the Battle of the Ruhr, Bomber Command severely disrupted German production. Steel production fell by 200,000 tons. The armaments industry was facing a steel shortfall of 400,000 tons. After doubling production in 1942, production of steel increased only by 20 percent in 1943. Hitler and Speer were forced to cut planned increases in production. This disruption resulted in the "Zulieferungskrise" (sub-components crisis). The increase of aircraft production for the "Luftwaffe" also came