a river running through a valley between mountains

Ruinaulta is a canyon created by the Anterior Rhine by Ilanz/Glion and Reichenau in the debris of the Flims Rockslide just upstream of its confluence with the Posterior Rhine at Reichenau in the Grisons, eastern Switzerland. It is sometimes known as the Rhine Gorge, or sometimes rather ironically called the Swiss Grand Canyon. Protected by cliffs several hundred metres high, the area is forested and a haven for wildlife.