It was added to the UNESCO list of World Heritage Sites in June 2002 because of its beauty as a cultural landscape, its importance as a route of transport across Europe, and the unique adaptations of the buildings and terraces to the steep slopes of the gorge.

The gorge was carved out during a much more recent uplift to leave the river contained within steep walls 200 m (660 ft) high, the most famous feature being the Loreley.

The river has been an important trade route into central Europe since prehistoric times and a string of small settlements has grown up along the banks.

It was at the centre of the Thirty Years' War, which left many of the castles in ruins, a particular attraction for today's cruise ships which follow the river.

The annual Rhine in Flames festivals include spectacular firework displays at Sankt Goar in September and Koblenz in August, the best view being from one of a convoy of boats.