Top 10 Interesting Danube River Facts

This mighty river flows through a large number of European countries and multiple major cities have been constructed on its banks.

Needless to say that this river has played an important role in the history of the continent as it formed the natural border of the Roman Empire for numerous centuries.

Let’s take a closer look at some of the most interesting facts about the Danube River, one of the most important rivers in Europe.

1. It flows from the Black Forest to the Black Sea

First things first, the Black Forest in Germany and the Black Sea that borders both Europe and Asia. The river emerges in the amazing forests of this mountain range in Germany and flows southeast, all across Central and Southeastern Europe, to the Black Sea.

The source of the Danube River is located in the German town of Donaueschingen, the place where the confluence between two small rivers called the Breg and Brigach is located.

This town was named after the river and is situated in the utmost southwestern part of Germany in the state of Baden-Württemberg.

confluence of Breg and Brigach
The confluence of the Breg and Brigach rivers / Drombalan / Wiki Commons

2. It’s the second-longest river in Europe

The ever passes by 10 countries in Central and Southeastern Europe before releasing in the Black Sea. It has a total length of 2,850 kilometers (1,770 miles).

This makes it the second-longest river in Europe after the Volga River which is entirely situated within the borders of Russia. This huge river has a length of 3,531 kilometers (2,194 miles).

The Danube flows through these 10 countries:

  • Germany
  • Austria
  • Slovakia
  • Hungary
  • Croatia
  • Serbia
  • Bulgaria
  • Romania
  • Moldova
  • Ukraine

The fact that the river flows through 10 different European countries ensures that it holds a remarkable river. It flows through most countries of any river in the world. The Nile River in Africa is second on this list as it flows through 9 different countries.

This long river emerges from a symbolic source that can be visited in the small town of Donaueschingen.

Donaueschingen Danube river source
The symbolic source of the river / Andredonau / Wiki Commons

3. The drainage basin of the Danube is huge

Another 9 countries are situated within the drainage basin of the river This basin is enormous as it covers an area of 801,463 square kilometers (309,447 square miles).

These 9 countries are located within this basin along with the area they cover:

  • Bosnia and Herzegovina (4.6%a)
  • Czech Republic (2.9%)
  • Slovenia (2.0%)
  • Montenegro (0.9%)
  • Switzerland (0.2%)
  • Italy (<0.15%)
  • Poland (<0.1%)
  • North Macedonia (<0.1%)
  • Albania (<0.1%)
Danube River facts

4. Multiple capital cities were built on the river’s banks

The Danube has been important throughout history and this is reflected by the fact that numerous cities emerged on its banks.

This includes both small villages and huge metropolitan areas, including 4 capital cities. These are the national capital cities through which the Danube flows:

  • Vienna (Austria)
  • Bratislava (Slovakia)
  • Budapest (Hungary)
  • Belgrade (Serbia)
Danube River in Budapest
The river in Budapest / Wiki Commons

5. The Romans were the first to build a bridge across the Danube

The Romans constructed a large number of architectural marvels throughout history. These ranged from amazing amphitheaters to Roman bathing complexes, as well as multiple bridges.

One of the greatest feats of engineering constructed during the Roman Empire was a bridge that crossed the Danube River in modern-day Romania and Serbia.

This bridge is referred to as “Trajan’s Bridge” because it was commissioned by Roman Emperor Trajan in the early 2nd century A.D. It played a major part in the Dacian Wars, resulting in the expansion of the Roman Empire to the east.

Although the bridge was only active for 165 years, it was the longest arch bridge constructed in the world for over 1,000 years.

Trajans bridge danube river
How Trajan’s Bridge might have looked like / Rapsak / Wiki Commons

5. It features the largest river island in Europe

Multiple large and small islands are located within the river. Many of these islands are uninhabited but several of them within borders of cities do have people living here.

Just southeast of Bratislava in Slovakia there’s an enormous river island called “Žitný Ostrov” or the “Great Rye Island.”

About 72,000 people live on this river island as it covers an area of 1,886 kilometers (728 square miles).

With a length of 84 kilometers (52 miles) and a width of anywhere between 15 and 30 kilometers (9.3 and 18.6 miles), it’s by far the largest river island in Europe.

LIttle Danube River island
The Little Danube which forms the river island / Michal Zuber / Wiki Commons

6. The Danube is connected to the North Sea

One of the most interesting facts about the Danube River is that it’s connected to the North Sea in the northwestern part of Europe. This connection is made possible via the Rhine-Main–Danube Canal near Nuremberg in Germany.

This canal has a length of 171 kilometers (106 miles) and connects the Danube with the Rhine River, the only river in the Alps mountain range that flows north.

This also means that it’s possible to travel from the Atlantic Ocean to the Black Sea. This relatively short canal that was completed in 1992 has made this happen, quite astonishing!

Rhine–Main–Danube Canal
Rhine-Main–Danube Canal / Ermell / Wiki Commons

7. The Danube has numerous tributaries, including some major rivers

The Danube River has a total of 32 tributaries and the top 3 of these are nearly 1,000 kilometers long. These are the Save, Tizsa, and Prut Rivers.

The confluence of the Sava, a river that flows through Slovenia, Croatia, and along the border of Bosnia and Herzegovina, and the Danube happens in Belgrade, the capital city of Serbia.

Sava and Danube Confluence
The confluence of both rivers in Belgrade / Petar Milošević / Wiki Commons

8. The Danube’s water completely disappears in some areas

The river starts as a small stream near its source in the German state of Baden-Württemberg. In the Swabian Alps, part of the river completely disappears below the surface in a natural phenomenon referred to as the Danube Sinkhole.

Between the small towns of Immendingen and Möhringen, there is hardly any trace of the river in an area locally known as the “Donauversickerung.”

The river disappearing into the river bed happens in several places in this area, only for it to resurface about 12 kilometers (7.5 miles) south of a spring called the Aachtopf.

Danube Sinkhole
The Danube Sinkhole / Drombalan / Wiki Commons

9. This national park in Romania features amazing gorges

The view of the river in the cities through which it flows is amazing, but nothing beats the landscape at the Iron Gates Natural Park in the southwestern part of Romania.

The Iron Gates is the name of a marvelous canyon that was carved into the landscape by the Danube. It’s the centerpiece of a natural park that covers an area of 115,666 hectares (285,820 acres), the second-largest of its kind in Romania.

The view of the river with the cliffs in the background is one of the most amazing you’ll find in Eastern Europe.

Iron Gates National Park
The Iron Gates National Park / Wiki Commons

10. The Danube Delta is a UNESCO site that supports many migratory birds

The second-longest river in Europe also features the second-largest delta on the continent. The largest part of this immense delta is located in Romania while part of it is situated in Ukraine.

The entire delta covers an area of 5,165 square kilometers (1,994 square miles) and it’s the best-preserved of its kind in Europe.

This also means that it features an abundance of wildlife. Over 300 species of migratory birds visit the delay, including some rare species such as the endangered pygmy cormorant (Phalacrocorax pygmaeus).

The most common birds you can spot inside the Danube Delta are pelicans, including the great white pelican (Pelecanus onocrotalus) and the Dalmatian pelican (Pelecanus crispus).

The Danube Delta has been a UNESCO World Heritage site since 1991 and an important Ramsar site as well.

Danube Delta great white pelicans
Great white pelicans having a great time in the Danube Delta / Wiki Commons