The great Cattedrale di Santa Maria Assunta (built in the 13th century over another Cathedral), one of the biggest in Piedmont, in Romanesque-Gothic style. The monumental belfry is from 1266. the facade is characterized by three portals, each surmounted by a big rose-window. The interior, with a nave and two aisles, houses a wide cycle of 18th century frescoes, some altarpieces by Gandolfino d'Asti and precious silver artworks from the 15th-16th centuries. The presbytery has a noteworthy mosaic floor, from the pre-existing church. next to the last pilasters of the nave are two 14th century artworks, the funerary seal of bishop Baldracco Malabaila and the equestrian portrait of Arricino Moneta.