Their northern section runs in an east-west direction roughly from the territory of Bramsche (northwest of Osnabrück) via Ostercappeln, Bad Essen, Preußisch Oldendorf and Rödinghausen, Lübbecke, Hüllhorst and Bad Oeynhausen as far as the towns of Minden and Porta Westfalica on the Porta Westfalica gorge and River Weser.