The restoration of one of the oldest parts of the Santa Maria presbytery made it possible to open a new museum in 2009. It is a rich and valuable collection of works mostly taken from the treasure of the Cathedral, added to which are stone finds, groups of terracotta statues, reliquaries, sacred vestments and medieval illuminated manuscripts coming from the capitulary historic archive of the city.
The museum, divided up into 12 exhibit halls, looks onto the inside courtyard where the old main well and a small stone basin fountain have been restored. The groups of clay statues proposing the sequences of the Passion of Christ with true-to-life theatrics are particularly moving. Of special note are the ivory diptych that belonged to a Roman aristocrat (5th century A.D.) with a list of bishops of Novara in sequence on the back, and two rare collections exhibited for the first time: one of Roman coins and the other of ancient vases of Magna Graecia dating to the 4th-2nd centuries B.C. The entrance to the Stone Museum is located in the last hall of the museum.
It is partially arranged beneath the pointed arches of the cloister, containing votive areas, sarcophaguses, sacred epigraphs and architectural elements found in the city and in the surrounding area. Some of the most valuable finds are the Celtic stone of San Bernardino of Briona, a stone head coming from the Dulzago Abbey, also of Celtic origin, the Appia Faventina plaque and lastly a superb 3rd century Roman sepulchral relief with a ship pictured on it.