 On 1 April 1850, even before it had completed its line, the RCG, together with the AND, was nationalised by the Prussian government and became part of the "Royal Directorate of the Aachen-Düsseldorf-Ruhrort Railway Company" ("Königliche Direction der Aachen-Düsseldorf-Ruhrorter Eisenbahn").On 1 January 1866 this company was taken over by the Bergisch-Märkische Railway Company (BME), which was also mostly state-owned.The BME opened a line in 1862 from Mülheim-Styrum station on its Witten/Dortmund–Oberhausen/Duisburg line to Duisburg-Ruhrort and remarked the distances along its track in kilometres from Aachen RHE station (km 0.0) to Dortmund (km 164.3).