From Regnano Villa (655 m), we continue on trail n° 11 Trekking Lunigiana to the location Il Castello, where the road turns sharply left and climbs to an altitude of 828 m. Here it turns right and ascends the Costa Miserino, going under Monte Peci until reaching Passo Cadin (930 m). From here, we descend on a dirt road towards Po' (there's an optional variant 200 meters away to see the beautiful potholes of Mommio, a route for experts), deviating after about 1 km from the direct itinerary towards this last hamlet in the direction of Mommio. We cross the homonymous river until we arrive, walking along the road, at Castiglione (912 m), passing first through the last houses of the village of Mommio and then climbing alongside the agritourism Restì. From Castiglione, we cross the Fusicchio Canal and continue on the trail, crossing the Fusicchio Canal again, along with the Fontana d’Oro Canal and the Rame Canal, as we ascend the slope that soon becomes very steep, until we reach the fork with trail n° 94A. We continue on trail n° 11 TL, skirting Giogo di Vendaso, and descend to the road. Unfortunately, here we have to walk a bit on asphalt, so we enter the road and continue to the right; after about 300 m, we take the road that descends to Sassalbo and reach it. Here we take trail n° 98 which, ascending, crosses the Torrente Rosaro (1,137 m), follows Lago Lungo (1,190 m) and arrives at Passo del Cerreto (1,261 m) where we reconnect with Sentiero Italia. At Passo del Cerreto, a pass of the Tuscan-Emilian Apennines that separates Tuscany from Emilia, specifically the province of Massa-Carrara from Reggio Emilia, there are several accommodation structures.