The Stone of Gronw. In the Welsh legend, Blodeuwed - wife of Lleu Llaw Gyffes - runs away with her lover, Gronw Pebyr, after a botched attempt to kill her husband. Later, Lleu Law and Gronw meet on opposite sides of a river. Lleu throws us spear at Gronwr, who hides behind a rock. The spear goes right through the rock and kills Gronwr, leaving a small circular hole in the stone.