The Tristan Stone

http://www.kingarthursknights.com/structures/tristanstone.asp 

Cornwall, England

Beside the road leading to Fowey in Cornwall stands an ancient, weathered stone measuring some 7 feet in height and set in a concrete base. It was once much closer to Castle Dore and may have been the origin of the association 

A memorial to the hero Tristan stands beside the road near the Cornish town of Fowey.

of this site with the story of the tragic love of Tristan and Iseult. There is a Latin inscription on the stone, now much worn, which can be restored with only a little judicial guesswork to read:

Drustans hic iacet Cunomori filius

This means:
Drustanus lies here, the son of Cunomorus
It has been suggested, plausibly, that the characters referred to are Tristan, the nephew of Mark - Drustan being a recognized variant of the hero's name and Cunomorus being a Latinization of Cynvawr. Cynvawr, in turn, is said by the ninth-century author Nennius, who compiled the best historical account of Arthur, to be identified with King Mark.