The Piccolomini Library, the vault: spandrel above the south - west wall between  the ninth and the tenth story, frescoes attributed to Girolamo del Pacchia, Giacomo Pacchiarotto and Littifredi Corbizi. The decoration is inspired by the Domus Aurea and the motif of the ancient grotesques. The general scheme of the vault is probably due to Bernardino di Betto, known as Pinturicchio. At the centre grisaille with combat between a warrior and centaur.