Largest tributaries
The Erft a river in North Rhine-Westphalia, Germany. It flows through the foothills of the Eifel, and joins the Lower Rhine (left tributary). Its origin is near Nettersheim, and its mouth in Neuss-Grimlinghausen south of the Josef Cardinal Frings Bridge. The river is 106.6 kilometres (66.2 mi) long, which is significantly shorter than it was originally. Due to the open-pit mining of lignite in the Hambacher Loch, the flow of the river had to be changed.
