This is a fairly challenging trail, as it often winds upwards; it starts in the hamlet of Valtopina, which was founded around the year 1000 AD on the river Topino, next to the Roman road "Flaminia". The hamlet is surrounded by remains that date back to the pre-Roman, Roman and early Christian periods: the most outstanding are Pieve Fanonica, which was originally an early Christian sanctuary, and the bridge on the Flaminia Way, with its imposing basement and several other interesting constructions. On the surrounding hills you will find interesting historical traces, such as the castles of Poggio, Serra and Gallano, the tower of Capodacqua and the Fortress of Calestro – corruption of the Latin place-name Galestrum. Most of these constructions were originally used by the Trinci – a family of noble Longobardian birth – as watch-places and strongholds, and they belonged to a vast defensive area spreading out as far as Visso. The Trinci family ruled the city of Foligno between 1305 and 1493 AD. Start your hike from the hamlet, taking the uphill path (n. 55) behind the last houses above the supermarket: at intervals, the path joins a winding tarmac road; walk as far as Casa Tommaso. Then take the uphill unsurfaced road through the woods, go past the remains of the castle of Serra; the road goes on downhill, until it reaches, after 100 m, a quadrivial crossroads, where you turn right. Stay on trail 55, walk as far as Vallemare. Take the tarmac road underneath, keep right, go past Case Colle Silvo, then walk on the path as far as a small tower, on your left, which is called "la Croce" – the Cross –, after which you take the tarmac road that leads to the wonderful hamlet of Armenzano. Its name comes from the Latin armentum, i.e. "herd", as sheep-farming used to be the main activity of the local population; it probably dates back to an early Umbrian period and was later extended in the 13th century. The houses are built on two concentric circles around the central castle, as a defence. After Armenzano, take trail 59 towards Notiano, a hamlet which is deeply rooted in the Franciscan tradition. After the village, you can follow the trail into the woods – as an alternative to the tarmac road – until you reach Molino Buccilli: this is the only operative mill of the Park and it is possible to visit it on request. From the mill you can easily walk back to Valtopina.