Rimaya

A rimaya in the Schnapfenspitze, in Tyrol, Austria.

Rimaya at the foot of Hintere Schwärze in the Alps of Ötztal.

A rimaya or bergschrund (Germanism used in glacial geomorphology) is a long, narrow and deep crack or cleft (crevasse) located at the upper end of a glacier of cirque, which forms when ice from moving glaciers separates from immobile ice on the escarpment.

In a cirque, the rimaya is located at the rear, parallel to the cirque's back wall and is caused by the rotational movement of the glacier. In a longitudinal glacier, the rimaya is at the upper end of the glacier, forming a right angle to the direction of advance and is caused by the downward movement of the glacier.

Rimayas can extend into bedrock and can be as deep as 100 meters.

In winter, the rimayas are often covered in snow from snow avalanches from the mountains above. In late summer, due to melting snow, they are open and can be a very difficult obstacle for climbers.

A rimaya is different from the randkluft (sometimes also called simply rimaya), which is the crack in which one of the faces is the rock itself, the back wall of the circus. The randkluft arises in part from melting ice due to the higher temperature of the rock face (Benn and Evans).