Architecture and Art. The Romanesque walls were rediscovered in 1905, when several pieces of the external plaster of the church fell off along Corso Porta Borsari and the City had to intervene for maintenance. On the advice of the rector of the time, the plaster was removed from the entire wall: thus the underlying wall in equally thick alternating layers of tuff and fishbone stones, with a basilica window, came to light. On the outside there is a marble burial site, with a cross and overlying triptych. The bell tower is built of brick: the basement was built in the 1300s, while the upper part is much more recent. On the inside there is a noteworthy base relief of the Madonna with Child, signed by Maestro Pulia and assigned to the late 1200s. The gem of the church is considered the renaissance door, sculpted by Gerolamo Giolfino, which bears on the sides of the arch and at its summit the statue of Saint John the Evangelist, Peter and John the Baptist, and in the niche there is the fresco by Nicola Giolfino with Saint John on the Island of Patmos.