The Museo dell’Opera del Duomo – literally the “Museum of Cathedral Works” – opened in 1986 in the former Episcopal seminary, or Seminario Vescovile. It was the outcome of a long museum project designed to display and illustrate the art of Pisa, and in particular its mediaeval sculpture, which had its roots in the centuries-old Piazza. The most important sculptures removed from the buildings during restoration operations carried out over the years, and especially during the radical nineteenth-century works, had until then been kept in city collections and in the storage facilities of the Opera della Primaziale Pisana.