The beech forests of Cuesta Fría cling to the north-facing slopes of the Valdeón valley, on the León side of the Picos de Europa, where the limestone mountains rise abruptly above the green of the Cantabrian coast. They are part of a group of old beech woods across Europe that UNESCO recognised for their natural value, because the trees here have grown with little human interference for a very long time. Posada de Valdeón, a village of a few hundred people, lies about five kilometres away.
Walking in them in October is one of the great autumn experiences of northern Spain. The trunks are grey and smooth, the leaves turn copper and gold and carpet the ground, and the light comes down through the canopy in long beams. Wolves, roe deer and the rare brown bear live in these mountains, and the capercaillie, a big woodland grouse, survives in small numbers, though you will be lucky to see any of them. The Cares gorge, the famous trail between Poncebos and Caín, is not far, and its narrow path above the river is one of the most-walked routes in Spain.
Getting there is half the pleasure. From Cangas de Onís the road climbs through the Desfiladero de los Beyos, a narrow gorge of vertical rock with the Sella river far below, and then goes over the Puerto de Pontón, at about 1,280 metres, before dropping to the Valdeón valley. The corners are tight, the surface is good in places and patched in others, and in the gorge the road is cut straight into the rock with little room to spare. The weather is a gamble. Clouds sit low in the valleys in the morning, thunderstorms break in summer, and snow may close the passes from December through March, so check conditions locally.
Fuel is the practical issue, as the villages in Valdeón and Sajambre are tiny and may not have pumps. Cangas de Onís, twenty-four kilometres or more from the forest, has six thousand people and several stations, and you should fill up before entering the mountains. The area is famous for Cabrales, a strong blue cheese ripened in caves, and for cider and fabada, the bean stew, while the village of Posada has simple places for a hot meal. Summer is crowded at the Covadonga lakes, but Valdeón stays quiet, and autumn is the glory.