A change in the attitude of society towards nature and landscape (first established in the intellectual sphere and later adopted by institutions and other agents) operates in the evolution of the notion of heritage so that a territorial dimension of this concept emerges. Its consolidation is slow, both in the generalization of actions and in the conceptualization: it finds pioneering manifestations in the second half of the 19th century and is considered to be widespread since UNESCO’s Convention Concerning the Protection of the World Heritage, held in Paris in 1972. The later addition of the cultural landscape figure in the actions by this organization (1992) and the possibility of including mountain areas as World Heritage in a mixed natural-cultural type have stimulated the elaboration of this study. The purpose is to provide keys for the characterization and qualification of a mountain area already considered as a possible candidate in the UNESCO tentative list (Somiedo, NW of Spain) in order to highlight its potential as Word Heritage. Research in this sector is also presented as a test for the development of a model that could serve as a complement for candidacies in other mountain regions with profiles or categories related to the one analyzed here: transhumance and/or trasterminance landscape in Atlantic mountains. The adequacy of Somiedo, particularly Saliencia Valley and Royal Way of La Mesa (somedan strecht) as a linked centennial itinerary, is justified by the diversity of UNESCO criteria that can be met, reflecting the diversity of outstanding features associated with natural and cultural elements and phenomena. The result could be the starting point for a further task: the formulation of concrete measures for the preservation of fundamental material and immaterial elements and the conception of an integral management program.