Dry weather exposes treasures below Stithians Reservoir

Low water levels have uncovered prehistoric treasures beneath a Cornish reservoir.

A collection of cup-marked stones are among the artefacts to have emerged at Stithians Reservoir near Falmouth.

There is also evidence of medieval farmsteads and modern pottery on the shoreline that is usually under water.

Archaeoastronomer Carolyn Kennett visited the lake on Monday and said: "I have not seen the water this low in a long while."

According to South West Water, the level of the reservoir on 10 July was 57% of its capacity.

It is asking people to try and reduce water usage to keep the reservoir levels up.

Ms Kennett said: "What's interesting about the pre-history at Stithians is the amount of cup-marked stones. There are batches of them but they are really condensed together in a small area.

"It is probably the most amount of cup-marked stones in one area in Cornwall, so it is the biggest amount of pre-historic rock art that we have."

It is not known why the markings were made but it is likely to have been done "artistically", she said.

"Cup-marking is definitely late or mid-Neolithic and into the Bronze Age they would still be doing it, but it is incredibly difficult to date these type of things," she said.

The Bronze Age was about 4,000 years ago, with the Neolithic period predating it.

Ms Kennett said: "This year in particular they [water levels] are incredibly low. It's exposing some of the medieval farmsteads that were covered over by the reservoir when it was flooded.

"It is really interesting to see how much has been exposed."

She believes the flooded land "is why they have survived - they are in great condition".

Cup-marked stones, and other remains of buildings and roads are also known to be beneath Drift Reservoir near Penzance.

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