Historically, the most important event in the Picos de Europa was the Battle of Covadonga in around 718 AD, when the Spanish Christian nobleman Don Pelayo defeated a contingent of Moorish soldiers in battle. Legend has it that the Virgin Mary appeared in the cave of Covadonga to spur them on. Pelayo and his men began a landslide that buried the Moors beneath its rocks. The surviving Moors crossed both the western and central massifs to make their escape, only to be killed by a natural landslide near Espinama. Pelayo was declared king of Asturias. So began the "reconquest" of Spain, a process which took another 600 years before the Moors were finally expelled. In acknowledgement of this event, Covadonga is the second-most important pilgrimage site within Spain, after Santiago de Compostela. The Picos de Europa National Park includes the historic site of Covadonga, with its basilica and sacred cave, and was at first christened "Covadonga Mountains National Park". This park, created in 1918, covered the western massif - the central and eastern massifs were added in 1995, and the name changed accordingly.
People had been living in the mountains long before the reign of King Pelayo, however, due to the presence of caves for shelter and wild game for food. By the time the Romans arrived, the Celtic peoples were farming the area, eventually being brought beneath the Roman yoke after the Cantabrian Wars of 26 to 16 BC. The Romans built cobbled roads across the mountains, the best preserved example being the Portudera road from Arenas de Cabrales over to Sotres.
Most of the tracks and pathways within the Picos de Europa today, though, are due to the pastoral livelihoods of the local people - a way of life that still exists but is in decline. Farming has traditionally been the main activity in the area, although mining was important, and tourism is increasingly so. Local people moved their cattle, sheep, goats and horses from their low-altitude winter quarters in the valleys, to the mid-altitude pastures ("invernales"), then the high mountain pastures ("majadas"), a practice which may have begun during Neolithic times, and can involve up to 1000m of altitude gain. Many people never left the majadas from spring through to winter, remaining high in the mountains with their animals for 6 or 7 months of the year, living in clusters of small stone huts. Many such evocative settlements dot the area, testament to a hard life, and some are still used, but most are falling into disrepair. It was in these majadas that the region's renowned cheeses came into being - Cabrales from the area around Sotres and Bulnes, Gamoneu from the northern slopes of the Western Massif, and Picón from Tresviso in the Eastern Massif, to name just three. Networks of well-built routes join the majadas to the invernales, villages and homesteads, across cols and ridges and "sedus" (difficult passes), often achieving traverses which appear to be unlikely, verging on the impossible. It is feats such as these that remind us how wise and in tune with the nature of the mountains people have been, and can be. These routes and settlements, built with local natural materials and human hands, give a feeling of awe. The people of the Picos de Europa co-evolved with the landscape during millennia, grazing their livestock, cutting wood for building and burning, coppicing chestnuts and hazels, harnessing the power of water to grind their grain, and leaving their mark on the landscape in many ways, as it left its mark on them. It is this symbiosis of people and landscape that lends the area its inspirational quality.
As well as these pathways and cabins, other man-made structures show how the local people live and have lived. Seen in just about every settlement throughout the Picos de Europa, the wooden buildings standing high off the ground on rodent-proof stone stilts are granaries, known as hórreos - many of them are still in use and hung outside with maize and onions. Hidden in the chestnut coppices of the woods, you may also chance upon what appears to be a small circular stone hut - this is a cuerria, used for storing chestnuts as a winter food supply - the woods alongside the River Casaño above La Molina contain good examples. There are few watermills ("molinos") within the Picos de Europa, due to the steepness and dangers of the water-courses - of the handful that exist, the ruined mills across the river from Caín spring to mind.