A central Cantabrian tributary of the Pas, joining the parent river near Sarón. The Pisueña is often the cleaner and steadier half of the Pas system — narrower, more wooded, mixed limestone-and-sandstone bedrock, with classic pool-riffle-glide structure on the middle reaches around Villacarriedo and Selaya. Wild brown trout dominate; sea trout appear in the lower river within the legal calendar. Two SAIH stations (Puente del Diablo and La Penilla) frame the middle/lower stretches, so spate response is well constrained. Worth knowing for the days when the main Pas is too coloured or too low — the Pisueña often holds a fishable window when the Pas does not.
- Mixed
