The Sentino is a tributary of the Esino River, which springs at 750 m above sea level above the mountains of Gubbio, in Umbria.

The source gushes from the north-eastern slope of Madonna della Cima and initially flows through the hills of the pre-Apennines of Gubbio, collecting the influx of many small streams.

Having crossed the Apennines, the Sentino enters the Marche region through a valley dotted with hermitages and monasteries, including Sant'Emiliano in Congiuntoli, until it reaches the town of Sassoferrato: the ancient Roman city of Sentinum, from which it takes its name.

Continuing its course, the river meets the Fabriano pre-Apennines generating the imposing Frasassi Gorge, famous for the homonymous cave, which the Sentino in the past has contributed to its genesis.

[2] Once past the Frasassi Gorge, near San Vittore Terme, the Sentino concludes its 42 km journey by meeting the Esino River, of which it becomes its main tributary.