It rises to the north of Brockhampton, a village to the east of Cheltenham, and flows in a south/south-easterly direction through the Cotswold Hills via Andoversford, Withington, Fossebridge, Bibury, Coln St Aldwyns, Quenington and Fairford.

Extensive gravel pits between Fairford and Lechlade, now redundant, have been flooded to form the eastern component of the Cotswold Water Park.

[2] The river is host to many species of freshwater fish including brown trout and grayling.

[1] The Environment Agency measures the water quality of the river systems in England.

There are several components that are used to determine this, including biological status, which looks at the quantity and varieties of invertebrates, angiosperms and fish.