Stourhead is a 1,072-hectare (2,650-acre) estate at the source of the River Stour in the southwest of the English county of Wiltshire, extending into Somerset. The estate is about 4 km northwest of the town of Mere and includes a Grade I listed 18th-century Neo-Palladian mansion, the village of Stourton, one of the most famous gardens in the English landscape garden style, farmland, and woodland. Stourhead has been part-owned by the National Trust since 1946.

The River Stour is a 61 mi (98 km) river which flows through Wiltshire and Dorset in southern England, and drains into the English Channel. The catchment area for the river and its tributaries is listed as 480 square miles (1,240 km2).