Beaminster is a town and civil parish in Dorset, England, approximately 15 miles northwest of the county town Dorchester. It is sited in a bowl-sh…Beaminster is a town and civil parish in Dorset, England, approximately 15 miles northwest of the county town Dorchester. It is sited in a bowl-shaped valley near the source of the small River Brit. The population of Beaminster parish was recorded as 3,177 in the 2021 census.