Fornela Valley and the source of the Cúa Nature · Peranzanes, El Bierzo, León A valley with a strong character of its own within the protected area of the Sierra de Ancares, run through by the River Cúa, which rises at the spot known as El Cuadro. Bog cottongrass grows on its waterlogged meadows and capercaillie and wolf survive in its woods. Photo: Marco Aurelio (CC BY-SA 3.0) What to see and do in Peranzanes