The legend that Joseph of Arimathea retrieved certain holy relics was introduced by the French poet Robert de Boron in his 13th-century version of the grail story, thought to have been a trilogy though only fragments of the later books survive today.
In 1191, monks at the abbey claimed to have found the graves of Arthur and Guinevere to the south of the Lady Chapel of the Abbey Church, which was visited by a number of contemporary historians including Giraldus Cambrensis [REF].