Ribbon lake

[1] As such, a ribbon lake is one of a number of glacial landscapes, including arêtes, corries, rock lips, rock basins and terminal moraines.

Such a lake's formation begins when a glacier moves over an area containing alternate bands of hard and soft bedrock.

The sharp-edged boulders that are picked up by the glacier and carried at the bottom of the glacier erode the softer rock more quickly by abrasion, thus creating a hollow called a rock basin.

[1] A ribbon lake may also form behind a terminal or recessional moraine, both of which also act as dams, enabling water to accumulate behind them.

[citation needed] Examples of ribbon lakes include Windermere, the largest natural lake in England;[1] Panguipulli Lake, in southern Chile;[citation needed] Lake Washington, in the state of Washington;,[1] Lake Ruda Woda in northern Poland and Llyn Ogwen, in northwestern Wales.