The Sigmund-Thun Gorge is located next to the town of Kaprun, Salzburg, Austria. The area around Kaprun is mainly known as skiing and hiking destination. The gorge can be found at the end of the Klammsee, a reservoir that dams the Ache of Kaprun river. Over 14.000 years ago the whole area was one big glacier and when it declined a valley cut was uncovered and the Ache of Kaprun river ran through it and dug itself 32 metres deep into the ground over time. The gorge was made accessible with wooden catwalks by the local Nikolaus Gaßner in 1893. He was the one who gave the Sigmund-Thun gorge its name. Naming it after the governor of Salzburg at this time: Sigmund Graf Thun-Hohenstein. Rebuilt in 1992 the wooden catwalk is open for visitors between mid of May and end of September.