The source is located at Watterdingen in the municipality Tengen, district of Constance in Baden-Wuerttemberg.

The Biber is the largest tributary of the High Rhine on the stretch between Stein am Rhein and Schaffhausen.

Shortly after Thayngen, the Biber leaves Switzerland and flows through Bietingen and Randegg, where the Dorfbach joins, coming from Gottmadingen.

Then it crosses the border again and the last kilometers flow through the upper part of the canton of Schaffhausen, through the municipalities of Buch and Ramsen.

These animals probably came from the valley of the Thur, crossed the Rhine and gradually followed the Biber upstream.