Klamm

The Liechtensteinklamm near Sankt Johann im Pongau, Salzburg, Austria

A gorge is a narrow valley cut into solid rock. The geomorphological shape of the gorge occurs mainly in the Austrian and Bavarian language areas and describes a particularly narrow gorge in the mountains with partially overhanging rock faces. Due to the overhangs, the width of the valley is sometimes less in height than on the valley floor, which is completely filled by the river or stream .

properties

In a gorge, the water flows in places and at times quite rapidly - depending on the formation of the rock - mostly in very narrow places. There are gorges whose rock faces are only a few meters from each other in some areas. Due to the low level of sunlight, lumps of ice trapped between the rock faces can survive the summer far below the usual frost line . Because of the small cross-section, after heavy rain there is a risk of a rapid water level rise even outside the time when the snowmelts.

Emergence

A gorge is created when a flowing body of water cuts into the rock over a period of many thousands of years and deep gorges form - mostly through meltwater and scree from glaciers after the Ice Age . This is favored by the fact that smaller glaciers in side valleys were less able to excavate the rock due to their lower ice load than the larger glaciers in the main valleys (see hanging valley ). Thus, the difference in altitude to the local erosion base is initially relatively large, and the watercourses of these side valleys cut deeper and deeper into the rock through backward erosion down to the level of their receiving water. Hard rock is a prerequisite for the formation of a gorge . In the Bavarian Limestone Alps, their formation was also favored by the existing carbonate rock, which, in addition to mechanical erosion, is also subject to processes of chemical weathering by water. Compared to the long-lasting deep erosion , denudation on the sometimes overhanging gorge walls is insignificant, which creates the incisive shape and almost no slope erosion occurs.

Many gorges were made accessible to visitors by footbridges , bridges and galleries .

Endangering people

Due to their shape, rapid and at the same time strong water level increases are possible during storms, sometimes by a multiple of the normal level. This can result in a life-threatening situation for visitors to the gorge, since in a gorge it is usually only possible to escape on higher paths.