After passing through Sankt Georgen, the route continues alongside the river Brigach. After Villingen, the route starts to leave the Black Forest behind, and crosses the Baar lowlands. In Donaueschingen, the Black Forest Railway meets up with the Höllental Railway, which is second only to the Black Forest Railway in significance in terms of railways in the area. The route then parallels the Danube river, which is formed by the confluence of the Brigach and Breg rivers, until it reaches Immedingen.