In 1870-72, John Marius Wilson's Imperial Gazetteer of England and Wales described Blackmoor Vale like this:
BLACKMOOR-VALE, the valley of the Cale river, on the mutual border of Somerset and Dorset; southsouth-eastward from Wincanton toward Sturminster. It is flanked by hill ranges, often 4 miles asunder; and has a rich, tenacious, marshy soil, notable as pasture land, and for the vigorous growth of oaks. It was originally called White Hart forest, from an incident in a hunt by Henry III.
Blackmoor Vale is now part of North Dorset district. Click here for graphs and data of how North Dorset has changed over two centuries. For statistics about Blackmoor Vale itself, go to Units and Statistics.
GB Historical GIS / University of Portsmouth, History of Blackmoor Vale in North Dorset | Map and description, A Vision of Britain through Time.
Date accessed: 25th March 2017
Click here for more detailed advice on finding places within A Vision of Britain through Time , and maybe some references to other places called " Blackmoor Vale ".