From the parking area south of the castles' cliff, the trail no. 205 - running through the last vineyards of Valtellina - leads to the medieval ruins. In Castello Nuovo, admire the evocative view over Rupe Magna - the biggest rock with petroglyphs in Europe - and over the majestic Grosio hydroelectric power plant. After visiting the castles and engraved rocks, follow the path down the town, with the majestic church of S. Giuseppe first, then Villa Visconti Venosta across the street and behind, walking in the winding alleys, the church of S. Giorgio. On its left, take Pruneri street and reach the river, then take the Valtellina Trail and pass through Grosotto hydroelectric power plant to finally rest at the lake with fishing facilities. Take Molini street to come back to the town, pass the square left the Town Hall and turn right in Patrioti street full of ancient testimonies among which, in the background, the sanctuary of the Blessed Virgin of Grosotto, a true baroque masterpiece. Following the route, it is easy to come back to the starting point.