Romanic parish built in the Lombard era (7th – 8th centuries). The church, cloister and collegiate church (12th century) rise alongside the residences of the kings Theodoric (6th century) and Berengarius (9th century), of which the surrounding wall is extant today.
The chromatic combination of brick, cobblestones and soft stone is typical. 12th and 13th century frescoes of the Martino and Altichiero schools decorate the interior.
The crypt contains two ancient sarcophagi, one of which is from the 3rd century and the other of which contains the remains of the apostles Simon and Judas Thaddaeus (4th-5th centuries); fragments of frescoes (initial years of the 15th century) of the school of Altichiero.