 Because of the insecurity of the coasts and the malaria which was endemic in the marshes that surrounded the foot of the hill on which the cathedral stands, it was abandoned by the bishops.At the beginning of the 16th century the humanist Agostino Giustiniani, bishop of Nebbio, had the cathedral repaired.It was also at this time that the belltower was almost certainly added which was destroyed by the 19th-century restorers.