<Tr> <Td> Note: Distances are in kilometers, rounded to the nearest kilometer . Waterway distances are shown, not towpath distances . Country capitals are shown in bold . </Td> </Tr> <P> The Danube or Donau (/ ˈdænjuːb / DAN - yoob, known by various names in other languages) is Europe's second longest river, after the Volga . It is located in Central and Eastern Europe . </P> <P> The Danube was once a long - standing frontier of the Roman Empire, and today flows through 10 countries, more than any other river in the world . Originating in Germany, the Danube flows southeast for 2,860 km (1,780 mi), passing through or touching the border of Austria, Slovakia, Hungary, Croatia, Serbia, Romania, Bulgaria, Moldova and Ukraine before emptying into the Black Sea . Its drainage basin extends into nine more countries . The Danube river basin is the most biodiverse region in Europe, and is home to hundreds of fish species, such as pike, zander, huchen, wels catfish, burbot and tench . It is also home to a large diversity of carp and sturgeon, as well as salmon and trout . A few species of euryhaline fish, such as European seabass, mullet, and eel, inhabit the Danube delta and the lower portion of the river . </P> <P> Old European river name derived from a Proto - Indo - European * dānu . Other river names from the same root include the Dunajec, Dzvina / Daugava, Don, Donets, Dnieper, Dniestr, Dysna, Tana and Tuoni . In Rigvedic Sanskrit, dānu means "fluid, drop", in Avestan, the same word means "river". In the Rigveda, Dānu once appears as the mother of Vrtra, "a dragon blocking the course of the rivers ." The Finnish word for Danube is Tonava, which is most likely derived from the word for the river in Swedish and German, Donau . Up North there is also a river called Tana . Its Sámi name Deatnu means "Great River". It is possible that dānu in Scythian as in Avestan was a generic word for "river": Dnieper and Dniestr, from Danapris and Danastius, are presumed to continue Scythian * dānu apara "far river" and * dānu nazdya - "near river", respectively . </P>

Where does the river danube flow from and to
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