Three imposing limestone massifs form the Picos de Europa National Park, which stretches between the provinces of Asturias, Cantabria and Leon. Part of the Cantabrian Mountain range, in the north of the Iberian Peninsula, the park holds the title of Biosphere Reserve and its 64,660 hectares make it one of the largest protected areas in the country.

Over 200 of the peaks in this natural paradise rise to over 2,000 metres. There are deep valleys, ravines and gorges, beech and oak forests, green meadows and winding waterways. The unique flora and fauna make this a truly privileged place, where, in addition to beautiful scenery, centuries of history have written their story in its villages and its paths.

The Central Massif, with its snowy summits, peaks and crags, is the most rugged in the park, and here are to be found the highest peaks, including Torrecerredo (2,646 m), and others as emblematic as Naranjo de Bulnes (Urriello PICU) and el Pico Tesorero (2,570 m), where the boundaries of the three provinces meet. The Western Massif is the largest, and here the high lands lead on to hay meadows, forests, streams and, of course, the Covadonga Lakes. The Eastern Massif is both smaller in size and lower and offers the visitor the rich contrast of rugged rock and green mountain pastures.

Four rivers run from the highest peaks of the Cantabrian mountains to the valleys, forming spectacular gorges and canyons. The river Sella rises in Sajambre and passes through the Beyos gorge, and on through Cangas de Onis. The Cares, the fiercest of the rivers makes its way down between the Central and Western Massifs crossing the Picos by a narrow canyon known as Senda del Cares. The Deva has its source in Fuente De and flows on to Panes, leaving behind a magnificent gorge, the desfiladero de la  Hermida. Finally, the Duje river, which originates at the foot of the cliffs of Pena Vieja flows into the Cares at Poncebos.