Erosion caused the mountain to collapse and the vast, pale yellow and reddish rock basin to form, which becomes bigger every year. From the Grabenrad or the Illhorn (2,716 m) there are "fear inspiring" yet stunning views down into the Rhone valley.
Western Switzerland’s most important river originates in the Gotthard Massif – where the rivers Rhine, Reuss and Ticino also originate. On its westward course, the country’s best vineyards accompany it for a large part.
Beavers, frogs and butterflies, white willows and orchids: now the region at the confluence of the Thur and the Rhine has been returned to nature, wildlife is flourishing again.