Windermere gets its name from the old Norse, Vinandr mere (Vinandr's lake; so 'Lake Windermere' is actually tautologous). Encompassing 5.7 sq miles between Ambleside and Newby Bridge, the lake is a mile wide at its broadest point, with a maximum depth of about 220m. It's a nice place to hire a boat for the afternoon, but it is far and away the busiest of the lakes.
Windermere Lake Cruises offers sightseeing cruises, departing from Bowness Pier.
The lake's shoreline is owned by a combination of private landholders, the National Park Authority and the National Trust, but the lakebed itself (and thus the lake itself) officially belongs to the people of Windermere (local philanthropist Henry Leigh Groves purchased it on their behalf in 1938).
There are 18 islands on Windermere: the largest is Belle Isle, encompassing 16 hectares and an 18th-century Italianate mansion, while the smallest is Maiden Holme, little more than a patch of soil and a solitary tree.