The Blackmore Vale (less commonly spelt Blackmoor) is a vale, or wide valley, in North Dorset, and to a lesser extent South Somerset and southwest Wiltshire in southern England. The vale is part of the Stour valley. The vale is delimited by the Dorset Downs, a chalk ridge to the south; Cranborne Chase, chalk hills to the east; and the watershed between the Stour and Yeo valleys to the northwest (which generally follows close to the borders between North Dorset, South Somerset and West Dorset). The River Stour flows out of the vale at Blandford Forum in the southeast, a town sandwiched between the Dorset Downs and Cranborne Chase. The river flows into the vale north of Gillingham.
The vale is Thomas Hardy's "Vale of the little dairies", and books including Tess of the d'Urbervilles were set here; he also lived and wrote in Sturminster Newton for a time. Poet William Barnes also lived in Sturminster Newton. Douglas Adams and Robert Boyle lived in Stalbridge for part of their lives.
Land use in the vale is predominantly dairy farming, with many small farms dotted across the vale. Until it was closed in 1998 Sturminster Newton livestock market was the busiest weekly livestock market in Britain. There are also many small towns and villages in the vale: