At Monterano, on the ridge of a mountain close to Oriolo in the area of Lake Bracciano, stand the ruins of a church dedicated to S. Bonaventura. It is devised on a Greek cross ground plan and forms the projecting headpiece of a longitudinally oriented monastery (Pls 12a, 12b, 13b). A faded inscription was still visible in 1964 on the architrave of the main façade ‘MDCLX’, but there was space for about two or more numerals which had disappeared. The complete inscription was probably ‘MDCLXXVII’, the date when construction began by the order of the Principe Don Angelo Altieri, nephew of Pope Clement X. The building was for the Padri delle Scuole Pie, who were called to instruct the people of the rural district surrounding Monterano in such basic skills as reading and writing, and in the elements of the Christian religion. At that time the Altieri family had only recently moved into the area, having in 1671 purchased from the Orsini the site at Monterano and the late medieval baronial palace. The building of the church and convent after 1677 was accomplished in breve tempo according to a chronicle of 1760 referred to by Ottarino Morra.