Grasmere is one of the smaller lakes of the English Lake District. It gives its name to the village of Grasmere, famously associated with the poet William Wordsworth, which lies immediately to the north of the lake.
The lake is 1680 yd (1540 m) long and 700 yd (640 m) wide, covering an area of 0.24 mi² (0.62 km²). It has a maximum depth of 70 ft (21m) and an elevation above sea level of 208 ft (62 m). The lake is both fed and drained by the River Rothay, which flows through the village before entering the lake, and then exits downstream into nearby Rydal Water, beyond which it continues into Windermere.
The lake contains a single island, known as Grasmere Island or simply ‘The Island’. In 2017 this island was bequeathed to the National Trust.