Lime and dolomite - the formative rocks
The Gesäuse mountains are part of the Northern Limestone Alps, which, with a length of over 500 km and a width of between 30 and 50 km, extend from the Alpine Rhine to the Vienna Basin. As the name suggests, limestones and dolomites are the most widespread rocks of the Limestone Alps. Due to their height of up to 2369m (Hochtor), the Gesäuse mountains of the Hochtor, Buchstein and Reichenstein group are counted among the High Limestone Alps. The high relief energy - i.e. the difference in altitude between valley and mountain - makes the Gesäuse geologically interesting.
The glacier cut
About 2.4 million years ago, the ice ages began in the Eastern Alps due to global climate changes. From a huge glacier area which covered almost all of western Austria, a glacier stretched across the Enns Valley to the so-called “Gesäuseeingang” near Weng village. Here the ice dammed up and moved northeast over the Buchauer Sattel.
If you enter the Gesäuse from Admont, the transition becomes clearly visible. But even today, the processes which led to the formation of the Gesäuse mountains are still continuing: The slow uplift of the Limestone Alps as well as the eroding of Enns river into the rock fronts. Frost and ice break up the rock, wind and water shape the rock, and rubble heaps bear witness to the exposure of the rocks to the forces of nature.