Stein Glacier. View of Stein Glacier and lake in central Switzerland. Glaciers are huge ice bodies which flow slowly downslope from areas of snow accumulation. This is a valley glacier as it is confined within a valley. The surface of the glacier near the valley sides is covered in fallen debris. When glaciers reach a warmer area, in this case at about the altitude of the lake, they melt. Photographed from the Susten Pass.