The document describes several features of glacial erosion visible in the Nant Ffrancon Valley in Snowdonia, Wales. These include hanging valleys formed by differential erosion, truncated spurs where pre-glacial ridges have been removed, asymmetrical roche moutonnées with smoothed up-valley and jagged lee-ward sides, ribbon lakes in overdeepened parts of the valley floor, striations on rock faces from abrasion by debris in glacial ice, and U-shaped valleys broadened and deepened by glacial erosion. It also mentions corries, arêtes, pyramidal peaks, and diffluent cols shaped by glacial erosion.