crêtes

Crêtes are long, narrow ridges of high ground that separate adjacent valleys or drainage basins. They are a common feature in mountainous and hilly terrain and can extend for many kilometers. The term is widely used in French-language geography and is also found in English-language texts describing ridges or crests.

Crêtes form where rock of relatively resistant hardness remains after erosion of softer surrounding rocks, or where tectonic forces raise a crest that is then sculpted by weathering. Glacial activity can sharpen crests, producing knife-edge ridges known in English as aretes, while fluvial and mass-wasting processes may widen or alter the crest.

In contrast to other landforms, a crête often represents the highest continuous crest line of a ridge, marking a drainage divide between basins. Its orientation, elevation, and width vary from broad, gently sloping crests to narrow, steep arêtes.

Human activities on crêtes include hiking traverses, ridge-and-valley routes, and the construction of roads or telecommunication lines along the crest. The exposure of crests makes weather conditions more severe and influences local microclimates along the line of the crest.