Folklore

Maen Ceti
Dolmen / Quoit / Cromlech

At midnight, when the moon was full, young maidens would test the fidelity of the men they loved by offering the stone a cake baked from Barley meal and honey wetted with milk. They would then circle the stone three times on their hands and knees, knowing that if their man appeared before they finished their final circuit he would make a faithful husband.

source
explore-gower.co.uk/arthursstone.htm