The Sanctuary appears almost at the end, as it is sheltered by a grassy knoll: some tall trees surround it. The imposing complex, the church and the annexed buildings, is characterized by a certain harmony. The two bell towers are characteristic, giving grace to the façade that face East. The simple pylon that is preserved inside the sanctuary is ageless. In ancient times an unknown painter portrayed the sweet features of the Madonna and Child. Around 1650, the inhabitants of Viola, by dissolving a vow for having been freed from the scourge of the plague, decided to transform the pylon into a chapel; then the building was enlarged to the present size from 1884 to 1894. The dome was painted by Giovanni Borgna, a disciple of Castaidi, while the main altar in the shape of a small temple is the work of Manzo di Mondovì.