List of tributaries of the Danube
The Danube is Europe's second-longest river. It starts in the Black Forest in Germany as two smaller rivers—the Brigach and the Breg—which join at Donaueschingen, and it is from here that it is known as the Danube, flowing generally eastwards for a distance of some , passing through several Central and Eastern European capitals, before emptying into the Black Sea via the Danube Delta in Romania.
Danubian corridor
In paleontology and archaeology, the Danubian corridor or Rhine-Danube corridor refers to a route along the valleys of the Danube River and Rhine River of various migrations of Eastern cultures from Asia Minor, the Aegean region, the Pontic-Caspian steppe, etc., into the north and northwest of Europe.