| Alcock Tarn | |
| Location: | Cumbria, England |
| Coordinates: | 54.4622°N -3.0056°W |
| Type: | Lake |
| Pushpin Map: | Cumbria |
Alcock Tarn is a lake in South Lakeland, Cumbria, England. It is located high in the fells on Heron Pike,[1] roughly a mile and a half east of Grasmere.[2]
Alcock Tarn was originally known as Butter Crags Tarn and was enlarged by means of a stone and earth dam in the 19th century to a depth of about . The owner, a Mr Alcock of Grasmere, then stocked it with brown trout.[3]