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.
Rába
The Rába (; ; ) is a river in southeastern Austria and western Hungary and a right tributary of the Danube. Its source is in Austria, some kilometres east of Bruck an der Mur below Heubodenhöhe Hill. It flows through the Austrian states of Styria and Burgenland, and the Hungarian counties of Vas and Győr-Moson-Sopron. Its is long, of which about 100 km in Austria. It flows into a tributary of the Danube (Mosoni-Duna) in northwestern Hungary, in the city of Győr. Towns along the Rába include Gleisdorf, Feldbach (both in Austria), and Szentgotthárd and Körmend (in Hungary). In the early Cenozoic the river used to flow in the opposite direction, but tectonic uplift reversed this flow.