Cathedral - church of St. Nazario and Celso Martyrs

St Aloysius Gonzaga is the patron saint of this parish church, built by Giovanni Battista Groppi of Milan in 1761.

The solemn and luminous interior, with a nave, two aisles and a large transept, contains paintings, including a Saint Rosalia by Pietro Novelli and a Mystical Marriage of St Catherine by Camillo Procaccini, both of the early 17C.
At the base of the presbytery steps is the tomb of Marta Tana di Santena Gonzaga, mother of St Aloysius Gonzaga.