The Sierra Os Ancares stretches over the regions of León, Lugo and Asturias. In Lugo it comprises the municipalities of As Nogais, Becerreá, Cervantes, Navia de Suarna and Pedrafita do Cebreiro (on the French Route). Os Ancares is an area of ecological interest. The peaks that border it rise to 2,000 metres, and their singular appearance was caused by glacial phenomena.
The wild area of the Sierra remains intact, as well as the local ancestral customs, of ethnographical interest. The traditional architecture is represented by the "palloza", a prehistoric construction of oval ground plan, made of stone, wood and rye straw, which serves as house, straw loft and stable.
This wonderful site offers a wide variety of landscapes: forests, peaks or rivers that run towards fountains. The "fragas" can also be found (mixed forests of Atlantic species).
The varied species of the indigenous vegetation grow at different altitudes. The valleys are covered in ash trees, oaks and elms. The mountain summits are crowned by holly trees, maples, service trees and hazel trees. On the sierra peaks and sunny areas predominate the Quercus pyrenaica, birches, service trees and moors.
The fauna of Os Ancares includes some endangered species, such as the capercaillie, the bear and the marten.