Source of the Danube
As early as 1847 the following definition can already be found in the "Universallexikon des Großherzogtums Baden" (Universal Lexicon of the Grand Duchy of Baden): “Danube, the biggest river of Germany, rises at the Martinskapelle in a wild and lonely area of the Black Forest, is called Brege at its origin and forms the river Danube in Donaueschingen where it is unified with the Brigach." (German original: „Donau, der größte Fluß Deutschlands, entspringt bei der Martinskapelle in einer wilden und einsamen Gegend des Schwarzwaldes, heißt am Anfang Brege… und bildet erst in Donaueschingen, wo sie sich mit der Brigach vereinigt, die Donau.“)
Yantra (river)
The Yantra () is a river in northern Bulgaria, a right tributary of the Danube. It is long (the second longest Bulgarian tributary of the Danube, after Iskar) and has a watershed of .
The Yantra has its source from the northern foot of Hadzhi Dimitar Peak in Central Stara Planina, at . In its upper course, it is often called "Etar" (Етър), its older name. The river flows into the Danube close to Svishtov.