Ruhr (river) Ruhr (river) __notoc__ The Ruhr is a river in western Germany (North Rhine-Westphalia), a right tributary (east-side) of the Rhine. The source of the Ruhr is near the town of Winterberg in the mountainous Sauerland region, at an elevation of approximately 2,200 feet (670 m). It flows into the lower Rhine at an elevation of only 56 feet (17 m) in the municipal area of Duisburg. Its total length is , its average discharge is 79 m³/s (cubic metres per second) at Mülheim near its mouth. Thus, its discharge is, for example, comparable to that of the river Ems in
Ruhr breaks between the individual city boroughs. Thus the Ruhr is described as a polycentric urban area, which shares a similar history of urban and economic development. Because of its history, the Ruhr is structured differently from monocentric urban regions such as Berlin and London, which developed through the rapid merger of smaller towns and villages with a growing central city. Instead, the individual city boroughs and urban districts of the Ruhr grew independently of one another during the Industrial Revolution. The population density of the central Ruhr is about 2,100 inhabitants per square kilometre (about 5,400 per square mile)—low compared