DonauWelle: Donauversinkung (Danube Sinkhole) near Immendingen

On this route, you'll experience something unique in the world: Between Immendingen and Möhringen, the Danube simply disappears from the surface. On approximately 155 days a year – in spring and autumn – the river sinks completely, allowing you to hike through the riverbed dry-footed.

The water seeps away, flows southward through a constantly expanding cave system, and after an average of 60 hours, resurfaces at 10,000 liters per second in the Aachtopf, Germany's largest spring, twelve kilometers away – and from there flows into the North Sea. The water from the Danube only reaches the Black Sea for two-thirds of the year. This natural spectacle is caused by the limestone rock layers from the Jurassic period, which form a large part of the Swabian Alb.

This unique hike starts at the hiking car park in Immendingen. Right at the beginning, you'll hike through the natural phenomenon of the Danube Sinkhole. The trail then takes you through the Kirchtal valley in a gentle up-and-down direction. From a beautiful vantage point, you can see as far as Hegau and Lake Constance.

The trail continues past the Höwenegg volcanic crater with its naturally formed lake. You'll enjoy a leisurely hike through the Pfaffenwinkel forest back to the starting point. Along the way, you'll pass several lovely rest areas. If you don't want to carry your provisions, you can also stop for a break in Hattingen or at the starting point.