This article is about the river flowing through Wiltshire, Hampshire and Dorset. For the small river in the New Forest, see Avon Water. For other rivers called Avon, see River Avon.
It is sometimes known as the Salisbury Avon or the Hampshire Avon to distinguish it from namesakes across Great Britain. It is one of the rivers in Britain in which the phenomenon of anchor ice has been observed.[3] The Avon is thought to contain more species of fish than any other river in Britain.[4] Long-farmed pastures and planted, arable fields line much of the valley; an indication of the wealth these brought to landowners is in ten large listed houses with statutorily recognised and protected parks. Many prehistoric sites and broader "landscapes" are found on either side of the river, the largest being the World Heritage Site zone of Stonehenge, Avebury and Associated Sites, followed by the Old Sarum knoll fortification and the Thornham Down prehistoric and medieval landscape.
All the significant direct and indirect tributaries of the Avon, including the Nadder, Wylye, Bourne and Ebble, converge within a short distance around Salisbury.
The 17th-century navigation channel near Britford is still in water
Construction of a navigation from Salisbury to Christchurch was authorised by the River Avon Navigation (Christchurch to New Sarum) Act 1664 (16 & 17 Cha. 2. c. 12). Work began in 1675 and the route was completed in 1684, but it fell out of use around 1715.[7] Canalised channels were dug to straighten sections of the river, including one through Britford parish just below Salisbury; a lock survives on this section near Longford Castle, having been rebuilt in brick as a pound lock soon after the original flash lock was damaged by flooding in the early 18th century.[8]
Path
The Avon Valley Path follows the river between Salisbury and Christchurch.
Rights of way
Canoeists seeking lawful passage as high as Salisbury have attempted to invoke the 1644 Navigation Act in their favour.[9] However, the Act was subject to enabling works, most of which were never completed, hence the right is disputed. Responsibility for delivery was given to private undertakers in the names of Hodges, Bennett and Dennett, who were to fund the canalisation between the places. They were allowed to charge their investment at 10% interest rate and could take full commercial advantage, which tripartite agreements from 1684 and 1685 evidence. The House of Commons Journal of 31 January 1699 records that the freeholders, inhabitants and residents of Ibsley and Fordingbridge petitioned the House on the fact that they could not comply with the 1664 Act and were never likely to do so. The House sided with them and effectively declared its view of the law, the finality of which, lacking royal assent, the law of rights of way is unclear on but makes more likely the view that the Act became voidable as the works to canalise the Avon were never implemented. Indecisive court cases were brought in 1737 and 1772 to enforce the alleged but not exercised right (to benefit barge owners).[10][11]
The valley from north to south has the following houses with large parks and gardens, significantly funded in their original form by the rich, mixed agriculture from the little-wooded upper valley plains and sides:
In 1996 almost the entire river, from Patney (Wiltshire) to Christchurch, together with its tributaries the Wylye, Nadder, Bourne and Dockens Water, was designated as the River Avon System SSSI.[27]
