Arete, Knife-Edge Crest Landscape
This is a landform resembling a blade-shaped ridge formed by glacial erosion. During the development of two adjacent cirques or glacial valleys, their back walls continually recede, causing the cirques to become closer to each other. As a result, the watershed between the cirques narrows until a knife-edge crest or fish fin-like ridge forms, which is called an arête. The associated landscape is called a knife-edge crest landscape.