Poppi Castle, or the Castello dei Conti Guidi, the main building in the Casentino, known from 1191, was owned by the Counts Guidi. It has additions by Arnolfo di Cambio. It has a courtyard, an external staircase, its chapel with frescos and its library containing rare manuscripts and incunabula.[4] Hermitage of Camaldoli, the ancestral seat of the Camaldolese monastic order.