Couloir

This article needs additional citations for verification. Please help improve this article by adding citations to reliable sources. Unsourced material may be challenged and removed. Find sources: "Couloir" – news · newspapers · books · scholar · JSTOR (May 2017) (Learn how and when to remove this message)

A couloir (French: [ku.lwaʁ], "passage" or "corridor") is a narrow gully with a steep gradient in a mountainous terrain.^[1]

A couloir may be a seam, scar, or fissure, or vertical crevasse in an otherwise solid mountain mass. Though often hemmed in by sheer cliff walls, couloirs may also be less well-defined, and may often simply be a line of broken talus or scree ascending the mountainside and bordered by trees or other natural features. Couloirs are especially significant in winter months when they may be filled in with snow or ice, and become much more noticeable than in warmer months when most of the snow and ice may recede. These physical features make the use of couloirs popular for both mountaineering and extreme skiing.