'Eerie' prehistoric stones uncovered as water levels drop at Stithians Reservoir in Cornwall

A medieval farmstead has also been uncovered because of the low water levels Credit: Carolyn Kennett

Low water levels brought about by the heatwave have uncovered a number of mysterious prehistoric stones at Stithians Reservoir in Cornwall.

The artefacts, which have been exposed during the recent spell of dry weather, are believed to date back more than 4,000 years and have been carved with intriguing cup-shaped engravings.

There is also evidence of a medieval settlement and modern pottery on the shoreline which is usually under water.

It is not the first time the stones have become visible because of low water levels but Archaeoastronomer Carolyn Kennett, who has often visited the site, says she has never seen levels so low.

The artefacts have been engraved with mysterious cup shaped markings Credit: Carolyn Kennett

She said: "The water levels seem particularly low this summer and it's quite an eerie feeling walking along the foreshore and seeing all the evidence from past lives being exposed.

"I've never seen the water levels as low as this before, although others may have, it is a testament to the dry summer and hot weather we have been having this year."

It is difficult to date the stones and Carolyn believes they were carved during the Neolithic or Early Bronze Age period, although their purpose remains a mystery.

Carolyn Kennett added: "It is rare to find so many together in such a localised area in Cornwall.

"It is not known why they were created, they are a type of art and theories around them suggest they could have had a deeper significance than being simple artistic expression."