Sigmund Thun Klamm 21 km away The Sigmund Thun Klamm is a gorge in the local area of Kaprun in Austria. It is up to 32 m deep and 320 m long. The gorge was formed by the Kapruner Ache, fed mainly by the meltwater of several glaciers in the Hohe Tauern, and dates back to the last ice age. Address: Kesselfallstraße, 5710 Kaprun Phone: +43 681 84924737 Website: http://www.klamm-kaprun.at/