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.
Kammel
The Kammel is a river in Bavaria, southern Germany. The Kammel originates west of Mindelheim, in the district Unterallgäu, and flows generally north. It flows into the Mindel (left tributary) south of "Offingen at the Danube", east of Günzburg in the district Günzburg. So it is an indirect right tributary of the Danube. The difference in altitude between the origin and the mouth is 265 m.