An enormous river that is one of the longest in the world carves its way through 10 European countries. From the Black Forest to the Black Sea the river spans across continents as it spans more than 2,800km (1,740 miles).

Its waters pass through Germany, Austria, Slovakia, Hungary, Croatia, Serbia, Bulgaria. Its impressive size means the Danube is the second-largest river in Europe, beaten only by Russia’s Vogla. The Danube-Breg river system is the 31st longest in the world, with the Nile, which spans 11 countries, taking the impressive crown ahead of the Amazon River in South America.

The Danube starts in the Black Forest in south Germany before flowing south east and finishing in the Black Sea, straddling the border of Europe and Asia. It is home to four capital cities, Vienna, Bratislava, Budapest, and Belgrade, with its massive drainage basin extending into a further nine nations.

The river doesn’t just carve through the capital cities either, it has become a central part in their expansion, providing a natural defence system and a steady water supply that has helped their growth over the years. According to the Times of India the river has been a great trade lifeline for Europe.

It links to the Main–Danube Canal which connects goods to both the Rhine and the North Sea. These have meant that goods can transverse their way from the North Sea to the Black Sea thanks to the expansive waterway.

The river is also a source of power for families in Romania and Serbia thanks to the Iron Gate Dam. It has also become a cultural talking point thanks to Johann Strauss’s “The Blue Danube” waltz, subsequently inspiring generations of composers, poets and painters.

Historically the river was a major boundary for the Roman Empire. Castles, fortresses and kingdoms emerged along its banks across the centuries.

It has now become an economic powerhouse monitored by the Danube Commission. The organisation was formed to give nations access and safe navigation along the river’s waterways.

As well as being an economic hub, the Danube has now become popular with cruisers. In a YouTube video, Mark Soberman from the Digitalroamads said: “Most often you’re talking seven to eight days overall. The Danube is the grand capitals route, you’ve got these incredible cities, Vienna, Budapest, Bratislava, and you’ve got these hidden gems as well.”

Mark says many travellers often face a difficult decision between cruising along the Rhine or the Danube. He explained: “The Rhine [has] castles, vineyards, little storybook towns, it’s a different experience.

“If you want the castles, vineyards, and want to pull straight up into town, that’s probably going to be the Rhine. But for other people, it’s like, ‘No, I want classic European cities like Budapest’, which is incredible to sail into, and Vienna, which has incredible architecture and things to see.”