Elter Water is the smallest of the sixteen lakes in the Lake District and lies in the valley of Great Langdale just to the south of Chapel Stile near Ambleside. Its elevation above sea level is 187 ft (57 m). Its name probably derives from Old Norse meaning 'the lake frequented by swans'; and swans still inhabit the area, including Whooper swans which overwinter on this stretch of water. While navigation is prohibited on the lake, free fishing for trout, coarse fish and char is permitted. The primary outflow is the River Brathay which then descends south to join Windermere.