The church of S. Maria della Rocchetta, today called Nostra Signora delle Grazie, was built before 1291 downstream from the now destroyed monastery of S. Maria di Bano, very active in the 13th century. The site was already frequented by the Celts who often had sanctuaries in places rich in water. The Piota stream right near Rocchetta receives the Malpertuso tributary. Even the Gorzente, the Latin Gurgentum, flows into the Piota shortly before. Along these streams the Ligurians and then the Romans extracted gold from the gold mines. The Genoese Spinolas, lords of Lerma, were responsible for the expansions of the complex from the end of the 1400s to the 1600s. The Spinolas had turned to Nostra Signora della Rocchetta to obtain the grace of a long-awaited offspring. Reachable along a road marked by the aedicules of a Via Crucis dating back to the 19th century, the church stands in a dominant position on a puddinga spur overlooking the Piota stream. The complex, which in the Middle Ages hosted travelers along the road that connected Monferrato to Liguria through the huts of Marcarolo, confirmed its vocation for hospitality during the last world war when the chaplain Don Luigi Mazzarello hid there some Jews who had escaped the racial persecution (tombstone). Open to the public on the occasion of particular religious holidays, the church preserves frescoes from the 17th century which have recently been restored. The painting of St. Giovannino was donated to Don Luigi by Enrico Levi as a sign of gratitude, together with the St. Carlo Borromeo, while the large painting with the Vision of St. Bernard of Clairvaux clarifies the connection between the hospice for pilgrims and wayfarers , present in Rocchetta, and the nearby Cistercian monastery of Bano. Until the recent post-war period, the sanctuary was a destination for pilgrimages from the surrounding towns: the so-called "rogations" to beg for rain on the local crops.