The Danube flows through Vienna, Budapest, and Belgrade.
At about 2,850 kilometres long, the Danube is Europe’s second-longest river, after the Volga. It rises in Germany’s Black Forest and travels eastward through or along the borders of ten countries before reaching the Black Sea through the Danube Delta.
The river passes through four national capitals: Vienna, Bratislava, Budapest, and Belgrade. This makes it especially important in European geography and history. The Danube has supported trade, settlement, and political connections for centuries, while the delta at its mouth is one of Europe’s most important wetland ecosystems.