Ribbon Lake – Ribbon Lakes are shaped like a finger (long and narrow)

NOTE:

A ribbon lake is a long, narrow lake found in glacial valleys. They are formed in locations where the glacier moved over soft rock. Harder rock higher up the valley is left relatively untouched, so ribbon lakes form in the bottom where soft rock has been eroded by the glacier.

To remember the meaning of the term Ribbon Lake, use the following mnemonic:

The ribbon was decorated with pictures of lakes (ribbon lake) and wrapped around her finger (to remind her that ribbon lakes are finger-shaped). She even left the ribbon on when she played soft rock (to again remind herself that ribbon lakes form on soft rock).

Glaciers move over both hard and soft rock as they gouge out valleys. Softer rock is less resistant to erosion, so the glacier will carve it out more deeply. 

When the glacier retreats, water collects in these deeper areas, creating long, thin bodies of water called ribbon lakes.

Many of the lakes in Britain's Lake District are ribbon lakes. Windermere is a prime example.