Arnego River Nature · Rodeiro, Deza, Pontevedra Its upper course runs through the west of the municipality between alder groves and old mills before narrowing on its way to the Ulla; the valley it opens up preserves one of the best-preserved riverside forest corridors of the upper Deza. It rises at 800 metres above sea level at the Peña de Francia, in the Sierra del Faro, from the union of several streams, and ends its course at Brocos, where it joins the Ulla in the Portodemouros reservoir. Already documented as Arnego in the year 853, its name is thought to have a pre-Roman origin and a hydronymic meaning, related to the idea of flowing. Photo: Iago Casabiell González (CC BY-SA 4.0) What to see and do in Rodeiro