The Blackwater River is a 10-kilometre (6.2 mi) long river in the counties of Dorset and Devon, in the south-west of England.

It rises to the north of Marshwood in Dorset, flowing north and west to join the River Axe at a point north of Axminster in Devon.

For most of its length it forms the county boundary between Dorset and Devon.

This Devon location article is a stub.

You can help Wikipedia by expanding it.This Dorset location article is a stub.