The clear, blue-green waters of the River Cares have gouged a deep ravine between the Central and Western massifs of the Picos de Europa. Between 1916 - 1925 a canal and path to service it were blown out of the cliff face to syphon off the waters to feed the hydro-electricity station in Poncebos. The path was reconditioned in 1946. Today, the Cares Gorge path is the most popular walk in the Picos de Europa and impossible to get lost on. Its 12 km length can be started either in the north end at Poncebos (pronounced Ponthayboss) in Asturias or in the south at Caín (pronounced Cayeen) in the province of León.

Stout walking boots or shoes are necessary as the stone path is loose in places. (Mike Stuart has been known to walk it in his slippers, but this is not recommended). A good head for heights is recommended however as although the path is mostly about 1,5m wide, in some parts its width shrinks to around 1m, making passing other walkers slightly precarious. Be prepared to repeat a hearty "Hola" regularly in the busy months of July and August. Other possible obstructions are the goats that live on the hillsides. At times the path is above the canal, at times below, and occasionally the two meet. As you near Caín, coming from Poncebos, there are a couple of bridges to cross before you enter a set of dripping, low-ceilinged tunnels that bring you to the dam. Set aside a whole day if you want to walk all of the gorge up and down, the only practical way without vehicle support at the other end, or unless you just want to walk in a little way then head back. From Poncebos at 218m to Caín at 460m the route takes from three to three and a half hours at a steady pace, the first half an hour or so being uphill. Knock off half an hour for the return journey.

Look out for birds; Dippers, Griffon vultures and Wallcreepers (the latter tend to be found at lower levels in autumn/winter) and flowering plants; the insectivorous Large-flowered butterwort (right) and Globularia vulgaris, while you keep one eye out for the very friendly goats that pasture in the gorge.

The slideshow below gives a virtual walk of the gorge, starting from Poncebos and ending at Caín, with many thanks to Steve Hartgrove for supplying the photos which were taken towards the end of May on a Picos Rock and Snow walking holiday in the Picos de Europa with Adventureline.