It was already mentioned in 1132 in a Innocenzo III’s papal bull of 1132 as rural parish church of Grignasco and later, in 1151, a paper shows also the name of a certain "Martinus diaconus de Grignasco". Today, it is the cemetery church. In the Middle Ages, it was abandoned by the population searching more protection in the settlement at the foot of the San Genesio’s castle rather than staying in the unprotected flat area. Only some wall stretches showing a false mosaic web of stone and terracotta triangles remain from the ancient Romanesque structure. After having been reworked over the centuries, the present structure dates to the 18th century. In its interior under the choir of the organ, you can make out an inscription and fragments of frescoes referred to Angelo de Canta, dated 1539. The two 16th-century paintings on wood of San Gaudenzio’s school are quite interesting; they are placed in the 18th-century altar-piece of the high altar. Moreover, direct your attention to the painting of Francesco Gianoli depicting Saint John the Baptist between San Gaudenzio and San Carlo Borromeo (around 1650) and a copy (the original was stolen) of a work ascribable to the Carlo Francesco Novolone’s circle, representing Saint Anthony of Padua, the Child and Saint Anthony the Abbot