Geographys

Danube countries

The ten countries the Danube passes through or along on its way from the Black Forest to the Black Sea, more than any other river in the world, and four capitals on its banks.

10 countriesAs of September 2026Short notes, not sourcedSuggest a correction

The 10 countries shaded; the smallest are dots.

The Danube is Europe’s second-longest river, after the Volga, at about 2,850 km. It rises in the Black Forest in south-west Germany and flows east to a delta on the Black Sea. Ten countries lie on it, more than on any other river in the world, and it runs through four capitals: Vienna, Bratislava, Budapest and Belgrade.

For long stretches it is a border rather than running through a country: between Slovakia and Hungary, Croatia and Serbia, Serbia and Romania, and Romania and Bulgaria. Barges can follow it all the way from the North Sea, since the Main–Danube Canal, finished in 1992, links it to the Rhine.

A clue in The Grid: On the Danube →

The upper Danube3

From the source to the Hungarian plain.

  • Flag of Germany
    Germany

    The Brigach and Breg streams meet at Donaueschingen and become the Danube. It passes Ulm, Regensburg and Passau, where the Inn joins it, carrying more water than the Danube itself.

  • Flag of Austria
    Austria

    Flows past the vineyards of the Wachau valley and through Vienna, whose waltzes include Johann Strauss II’s “The Blue Danube”.

  • Flag of Slovakia
    Slovakia

    Bratislava sits on the river, and the Danube forms much of the border with Hungary. Bratislava and Vienna, about 55 km apart, are the two closest capitals in Europe apart from Rome and Vatican City.

The middle Danube3

Across the plain and through the gorges.

  • Flag of Hungary
    Hungary

    At the Danube Bend the river turns south and runs straight through Budapest, with hilly Buda on one bank and flat Pest on the other.

  • Flag of Croatia
    Croatia

    The river is the border with Serbia for most of Croatia’s stretch. Vukovar, badly damaged in the war of 1991, is on its bank.

  • Flag of Serbia
    Serbia

    The Sava meets the Danube at Belgrade. Downstream, the Iron Gates gorge on the border with Romania has two large dams built together by Yugoslavia and Romania.

The lower Danube4

The last stretch, to the delta on the Black Sea.

  • Flag of Romania
    Romania

    Has the longest stretch of the river, much of it as the border with Serbia and Bulgaria, and most of the Danube Delta, the second-largest river delta in Europe, after the Volga’s.

  • Flag of Bulgaria
    Bulgaria

    The Danube is nearly all of its northern border with Romania. Only two bridges cross that stretch, at Ruse and at Vidin.

  • Flag of Moldova
    Moldova

    Its bank on the Danube is only a few hundred metres long, at Giurgiulești, but it’s enough for Moldova’s only port for ships from the sea.

  • Flag of Ukraine
    Ukraine

    Its Danube bank is on the delta, where the Kilia branch is the border with Romania. During the war with Russia, the ports of Izmail and Reni became a way out for Ukrainian grain.

Close calls

Basin countries

Rain that falls in nine more countries drains to the Danube through its tributaries without the river itself going there, among them Switzerland, Italy, Poland, the Czech Republic, Slovenia, Bosnia and Herzegovina, Montenegro, North Macedonia and Albania. The basin has more countries than any other in the world.

The Black Forest source

Donaueschingen’s park has a spring, the Donauquelle, that’s often called the source. Geographers usually count the Breg as the true headwater, since it’s the longer of the two streams.

Where the river disappears

Near Immendingen, not far from the source, much of the young Danube drains underground in summer through the limestone and comes out again at the Aach spring, which flows into the Rhine by way of Lake Constance.

More country lists

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