The Patronal Church originally grew up as a chapel subordinated to the canons of the island of St. Giulio and was rebuilt in Romanesque style in the XII century with the dedication to St. Audenzio.
  In 1451 Pettenasco became an autonomous parish and acquired full autonomy under Bishop Bascapé, presbytery of Novara between 1593 and 1615. At the end of the year ‘500, the building was partly restored.
In the apse you can admire and appreciate the painting about the Mystique Wedding of St. Caterina. The protagonists of the painting are the Madonna with Child and St. Catherine kneeling at their feet in the act of receiving the ring surrounded by three pairs of angels.
Inside the church there are six chapels: the Crucifix, the Saints Julian and Audenzio, the Madonna del Rosario and the Saints Antonio of Padua and Giovanni Nepomuceno. This one holds the so-called "Madonna della neve con il Bambino", to which the inhabitants of Pettenasco were devoted well before the birth of the homonymous sanctuary in the hamlet of Pratolungo.
