The sacristy was commissioned by the Magnificent Pandolfo Petrucci, Lord of the City of Siena from 1487 to 1512, as his funerary mausoleum. The austere wooden choir carved by Antonio Barili in 1497 borders the walls while the extraordinary sculptural group in polychrome terracotta representing the Lamentation Over the Dead Christ, made by Giacomo Cozzarelli at the end of the fifteenth century, is . . .