History of the Ruhr History of the Ruhr The actual boundaries of the Ruhr vary slightly depending on the source, but a good working definition is to define the Lippe and Ruhr as its northern and southern boundaries respectively, the Rhine as its western boundary, and the town of Hamm as the eastern limit. In the Middle Ages, local power was vested primarily in the counts ("Grafen") of Berg, Mark and Cleves. The left bank of the Rhine was held by the Archbishop of Cologne. The Hellweg was an important trade route crossing the region from Duisburg to Dortmund and beyond as far as
History of the Ruhr warm and cold weather. During the Drenthe Stadium of the Wolstonian Stage, an ice sheet over Northern Germany covered the Ruhr and reached as far as the northern hills of the Central Uplands. The shape of the middle and lower Ruhr valley is due to meltwaters and the powerful force of the ice. Meltwater from the glaciers flowed westwards through the Ruhr valley. Where Essen lies today, this flow was temporarily hindered by a barrier of ice and rocky debris, forming an enormous lake which filled the valley at Schwerte. Large areas of the Ruhr come under Prussian control. Ironworks