Blackwater is a small town in the northeastern corner of Hampshire, England, lying in the county's Hart District. Considered to be part of the Farnborough/Aldershot Built-up Area and almost contiguous with Camberley, Surrey, it is centred 32 miles (51 km) WSW from London.

Hart is a local government district in Hampshire, England, named after the River Hart. Its council is based in Fleet. The district also contains the towns of Blackwater and Yateley, along with numerous villages and surrounding rural areas.