The ancient site, which dates back between 250,000 and 300,000 years to the early Stone Age, is thought to be of national importance.

Initial surveys suggested nothing of archaeological significance, but further investigations revealed a major historical site.

Archaeologists discovered a range of items, including 44 flint hand axes, which are the earliest form of tool used by man. Other finds included animal bones, such as horse bones.

Helena Cave Penny, Wiltshire County Council's county archaeologist for Salisbury district, said: "These finds appear to be of national significance. This is a very exciting discovery which has helped our understanding of the period.

"The presence of charcoal at the site suggests the people there made fires - this would seem natural when it is known that the climate was cold and damp at the time. It could be the earliest evidence of such fires in Britain and probably in Europe."

Archaeological evidence suggests the site was next to a tributary of the River Avon and may have been used as a seasonal riverside camp by hunters who lived in Britain at the time.

The need for a relief road to improve access to Churchfields Industrial Estate and take through traffic away from Harnham was identified by the Salisbury Transport Study, and the scheme was provisionally accepted for funding in December 2000.

Wiltshire County Council will now be consulting with English Heritage and other interested organisations to decide what steps should be taken to safeguard the archaeological finds.

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