The little Gothic church of Sant’Agostino was built in 1448, dedicated to Saint Sebastian, who was believed to have miraculously saved the city from the plague. It was later expanded into a monastery of the Hermits of St. Augustine, whose friars changed its dedication.
Originally a Sicilian-style late Gothic building, it was substantially changed around 1700, adding the bell tower and entrance arch replaced with the present entrance. Only the top of the arch and the small rosette above the door remain from the original church. It is now used as a public library. Its campanile is a small crenelated tower, and the door was added in 1700.
