Gillingham is a town and civil parish in the Blackmore Vale area of Dorset, England. It lies on the B3095 and B3081 roads in the North Dorset administrative district, approximately 4 miles (6.4 km) south of the A303 trunk road and 5 miles (8.0 km) northwest of Shaftesbury. It is the most northerly town in the county. In the 2011 census the civil parish had a population of 11,756. The neighbouring hamlets of Peacemarsh, Bay and Wyke have become part of Gillingham as it has expanded.