A skull discovered by a dog walker in Somerset dates back to the late Iron Age, archaeologists have revealed.
Roger Evans, of Newtown, found the skull along the banks of the River Sowy in Langport back in March 2017.
The skull was reported to the police and analysed, with months of tests finding that it belonged to a woman aged 45 or older during the late Iron Age.
This period stretches from 380-190BC - several centuries before the first Roman invasion of Britain.
Analysis by a human bone expert found that the skull had suffered from gum disease and tooth loss.
The woman's diet included coarse material, which had unevenly worn her remaining teeth and resulted in severe osteoarthritis in the joint of her right jaw.
She had suffered at least one episode of chronic illness or nutritional stress during childhood.
Her head appears to have been deliberately removed at, or shortly after, death.
Richard Brunning, archaeologist at the South West Heritage Trust, said: "Severed heads are not an unusual discovery for the Iron Age, but the placement of the skull in a wetland beside a wooden structure is very rare, possibly reflecting a practice of making ritual offerings in watery environments."
In December, the Environment Agency reduced water levels around where the remains were found to allow the South West Heritage Trust and an archaeologist to investigate.
Timber posts, driven deep into the river bed, were also discovered at the site and radio carbon dating is now being carried out to see if they are of the same period.
More posts were seen further down the channel, suggesting that other prehistoric wooden structures are present nearby.
Water levels have been returned to normal to protect the timber posts, along with any other archaeological remains still in the water.