There are several rivers named Stour in the United Kingdom. The most well-known is the River Stour that flows in East Anglia, running through the counties of Kent and Essex, eventually reaching the North Sea.
Queen Gwendolen and her husband King Locrinus of Britain, who had abandoned her for his mistress, fought each other near River Stour. Her husband was killed and Gwendolen ruled the country.
River Stour Locations
Dorset
Located in the county of Dorset, eventually reaching the English Channel at Christchurch.
Worcestershire and Warwickshire
Another River Stour flows through parts of Worcestershire and Warwickshire in the West Midlands.
Suffolk
There is a River Stour in Suffolk that flows through the town of Sudbury. This river is a tributary of the larger Stour that flows through Essex and Kent.
Cambridgeshire
There is a smaller River Stour in Cambridgeshire that flows through the town of Newmarket. It is a tributary of the River Cam.
Source
Historia Regum Britanniae | Geoffrey of Monmouth, c. 1138