Danube
Classified as an international waterway, it originates in the town of Donaueschingen, in the Black Forest of Germany, at the confluence of the rivers Brigach and Breg. The Danube then flows southeast for about , passing through four capital cities (Vienna, Bratislava, Budapest and Belgrade) before emptying into the Black Sea via the Danube Delta in Romania and Ukraine.
Baar (region)
The Baar contains the source of the Neckar (a bog in Villingen-Schwenningen) and the Danube. The sources of the Danube, the Brigach and Breg, originate in Furtwangen im Schwarzwald and Sankt Georgen im Schwarzwald and join the smaller Donaubach in Donaueschingen.