Devdaraki is a valley glacier

Glacier

A glacier is a large persistent body of ice that forms where the accumulation of snow exceeds its ablation over many years, often centuries. At least 0.1 km² in area and 50 m thick, but often much larger, a glacier slowly deforms and flows due to stresses induced by its weight...

 located on the northeastern slope of Mt. Kazbek. The length of the glacier is 5.5 km (3.4 mi) and its surface area is 7.13 km² (2.8 sq mi). The tongue of the Devdaraki Glacier descends to 2300 metres (7,545.9 ft) above sea level. Devdaraki is known for its intense surging

Surge (glacier)

Glacial surges are short-lived events where a glacier can advance substantially, moving at velocities up to 100 times faster than normal. Surging glaciers are clustered around a few areas. High concentrations of surging glaciers can be found in Svalbard, Canadian Arctic islands, Alaska and Iceland...

 properties that have caused significant destruction in the past (particularly from the late 18th to the late 19th centuries). The glacier surges have led to catastrophic mudflows in the Dariali Gorge which have, on several occasions damaged the Georgian Military Highway. The Devdaraki Glacier is the source of the River Kabakhi (left tributary of the Terek River).