But what has puzzled Dr Frieman and her team was the discovery of "unaccountable" medieval activity on the same site.Many ancient barrows and other monuments long retained their uncanny associations. At such places one might encounter the wee folk, ghosts, demons, or the devil himself. So it is hardly surprising that people might have returned to them to carry out sacrificial rituals.
She said: "The site has thrown up a big mystery for us because we found what we believe is an entire - albeit crushed - medieval pot from the 12th or 13th century AD, carefully placed under a couple of layers of flat stones. It had some cooked food remains adhering to it and we don't know what it's doing there or why.
"Hundreds of years after the barrow was built, someone from the 12th or 13th century came back to this site and dug into it to bury this pot.
"At that stage there were two local monasteries in view of this site, as Looe Island was a satellite monastery of the Glastonbury Abbey, so it would be very strange to have non-Christian activity on this site.
"The evidence looks quite ritualistic, but what the ritual was, we don't know."
As to Cornish people carrying out pagan rituals near a monastery, well, I'm certainly not surprised.