The River Cares rises in Valdeón (León) and flows mostly through Asturias, emptying its waters into the Deva at Panes (Peñamellera Baja).
At Poncebos it meets the Duje on the right, both of them adopting a fork-shaped course that embraces the whole of the Massif Central. Together they head towards Arenas, Cabrales, where the Casaño joins on the left.
Cabrales, Peñamellera Alta and Peñamellera Baja.
On its way through Asturias it flows through Arenas in Cabrales, Trescares and Niserias (Peñamellera Alta).
Its main tributaries are the Río Duje and El Casaño.