The longest river within today’s European Union – and second-longest on the continent – the Danube River originates in Germany’s Black Forest, and flows in a southeasterly direction through central and eastern Europe to the Black Sea. Strategically important as a means of transport and trade since the dawn of history, the river served for centuries as the northern frontier for much of the Roman Empire. A preferred route of travel by rulers since ancient times, the Danube has long been called “the river of kings.”


Length: Approximately 1,785 miles / 2,872 kilometers

Source: Donaueschingen, Germany, in the Black Forest

Mouth: In the Danube Delta of Romania, at the Black Sea

Oldest Trade Routes
Ancient Greeks navigated up the Danube from the Black Sea, as far as the Iron Gate. Later, river transport was developed by the Romans; many cities along the Danube began as Roman military outposts. In medieval times, goods were moved either by boat or barge, or along its banks, fostering development of the Habsburg and Hungarian empires.

The Danube flows through ten modern-day European nations: Romania, Hungary, Serbia, Austria, Germany, Bulgaria, Slovakia, Croatia, Ukraine, and Moldova

UNESCO World Heritage Sites in the Danube River Region

  • Austria: Historic Centre of Salzburg; Schönbrunn Palace; Wachau Cultural Landscape; Historic Centre of Vienna
  • Czech Republic: Historic Centre of Cesky Krumlov; Historic Centre of Prague
  • Germany: Old Town of Regensburg
  • Hungary: Budapest / Danube Banks; Early Christian Necropolis of Pécs (Sopianae)
  • Romania: Danube Delta; Villages with Fortified Churches in Transylvania