A narrower definition places the limits of the vale close to the county boundary and villages like Bourton, where the landscape transitions to hillier greensand, limestone and sandstone geology.
[3] In her book on the Blackmore Vale, Hilary Townsend described the northern boundary as "above Gillingham, through Motcombe to Queen Oak and Bourton, then crosses the A303, ignores the A30 and slips down on winding country roads past Bow Brook and Gibbs Marsh towards Sherborne"; while she placed the western boundary outside the Stour watershed "south of Sherborne down Dancing Hill, across the A352 and pick up the line of the River Yeo towards Beer Hackett, Yetminster and Chetnole".
[4] 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 majority of human settlements are built on the drier strips of limestone, whereas the more poorly draining clays (which comprise the greater bulk of the area) are more sparsely populated,[6] supporting mostly small farms, dotted across the vale.
[7] The vale, in particular the village of Marnhull ("Marlott"), is the opening backdrop for Thomas Hardy's Tess of the D'Urbervilles;[8] he also lived and wrote in Sturminster Newton for a time.