The River Dun is a river located in England, primarily flowing through the counties of Berkshire and Hampshire. It is a tributary of the River Test, which eventually joins the River Itchen. The river is approximately 20 miles long and is known for its scenic beauty and diverse wildlife. The River Dun is popular for various recreational activities, including fishing and walking along its banks. It supports a range of habitats, making it an important ecological area. The river also plays a role in local agriculture, providing water for irrigation in the surrounding fields.