It crosses the communes of Alzi, Bustanico, Campi, Linguizzetta, Matra, Mazzola, Moïta, Pianello, Tallone, Tox and Zalana.

About 1 kilometre (0.62 mi) after Matra there is a lookout point from which a 20-minute hike along a trail leads down to the magnificent Genoese bridge of Aliso.

[3] A five-minute walk upstream of the bridge along the river leads to the Bravone waterfall, set in an ancient forest, which falls into a large, deep basin.

The contamination was due to intensive exploitation of an arsenic mine at the start of the 20th century on the banks of the Presa tributary near the village of Matra.

Although levels of contamination drop further downstream, even at its mouth it is three times higher than is allowed by French and European regulations.