 Copies of the Chartres labyrinth are found at other churches and cathedrals, including Grace Cathedral, San Francisco.The Chapel of Saint Piatus of Tournai was a later addition to the cathedral, built in 1326, close to the apse at the east end of the cathedral.It contained a collection of reputed relics from the saint, who was bishop of Tournai in modern-day Belgium in the third century, as was martyred by the Romans, who cut off the top of his skull.