In Pale, the river drowns in the valley below it forming a series of tidal waterfalls surrounded by dense vegetation.
The river originates from the sources of the Favuella trench, at an altitude of 800 meters above sea level, near the town of Orsano (the mountain village of Sellano, 30 km from Foligno) and Mareggia Mountain. Near the city of Rasiglia, the river is enriched with a certain amount of water from the tributaries and can be poured into the homogeneous valley, at an average height of 530 m.
Although in small numbers, it is still possible to find samples of trout and crayfish at the top.