The Hampshire Avon rises in Wiltshire’s Vale of Pewsey as two streams that merge at Upavon, then flows south across Salisbury Plain through Amesbury and the historic city of Salisbury, famed for its cathedral and water meadows. From there, it enters Hampshire, meandering through the Avon Valley past Fordingbridge and Ringwood, skirting the western edge of the New Forest, before joining the River Stour and reaching the English Channel via Christchurch Harbour in Dorset. At 96 km long, it is predominantly a chalk stream, with clear, mineral-rich waters supporting exceptional biodiversity.

Flora includes aquatic plants such as water-crowfoot (Ranunculus species), starwort, and water moss, while its margins host sedges and wetland vegetation. The Avon is internationally important for wildlife, designated as a Special Area of Conservation and Ramsar site. It supports species like Atlantic salmon, brown trout, sea and brook lamprey, and the rare Desmoulin’s whorl snail. Birdlife includes kingfishers, herons, and wintering wildfowl.

Notable landmarks along its course include Stonehenge and Old Sarum near its upper reaches, Salisbury Cathedral, and the scenic Avon Valley Path. Christchurch Harbour at its mouth is a hub for recreation and nature conservation, marking the river’s transition from pastoral landscapes to the sea