Between Bingen and Bonn, Germany, the river Rhine flows as the Middle Rhine through the Rhine Gorge, a formation created by erosion, which happened at about the same rate as an uplift in the region, leaving the river at about its original level, and the surrounding lands raised. This gorge is quite deep, about 130 metres from the top of the rocks down to the average water-line.
The "Middle Rhine" is one of four sections of the river between Lake Constance and the North Sea. The upper half of the Middle Rhine from Bingen to Koblenz is a UNESCO World Heritage Site with more than 40 castles and fortresses from the Middle Ages and many wine-villages. The lower half from Koblenz to Bonn is famous for the formerly volcanic Siebengebirge with the Drachenfels volcano. Both parts together are known as "the romantic Rhine".
The Middle Rhine Valley has been a major tourist attraction since the 19th century. It is also home to some 450,000 people. The valley owes its special appearance to both its natural shape and human alterations. For two millennia, it has been one of the most important routes for cultural exchange between the Mediterranean region and northern Europe.