The cathedral, which is the main church, has origins dating back to the early years of Christianity, although little remains of the original structure. The Romanesque bell tower is a remnant of the rebuilt structure (likely commissioned by Matilda of Canossa), while the rest of the church was reconstructed in the 15th century during the rule of the Gonzaga family.

The neoclassical façade, made of Carrara marble, was added in the 18th century. The interior decorations by Giulio Romano are part of the restoration work carried out after a fire in 1545. One of the most impressive works is “The Temptations of Saint Anthony” by Veronese.

Additionally, the church houses the tombs of prominent city figures from its past, as well as many members of the famous Gonzaga family.