As mentioned in the introduction, the hike is very easy and safe, despite the warning signs. The starting point is the bridge near the football stadium, which is very easy to find.
(S/E) With your back to the bridge, follow the Porto River on your left, then turn away from it. You will arrive at the Ravin de Furtolaccia stream.
(1) Continue and join the Zaglia Bridge.
(2) Reach the riverbank.
(3) Turn around and follow the same route back to the car park (S/E).