The Oscos-Eo Biosphere Reserve was declared as such by the UNESCO in 2007, becoming the first to be awarded this distinction outside the network of protected nature areas. It also has the distinction of being the first to be shared by two autonomous communities, Asturias and Galicia.
The reserve encompasses seven boroughs in Asturias and covers a total of some 1,600 square kilometres, where approximately 34,000 people live. These are lands joined and associated by the "axis" of the Eo River and its estuary.
The area boasts a great variety of scenery. What's more, its rich natural heritage associated with the mouth of the Eo and the valleys of the river basins that make up this area allow visitors to enjoy beautiful beaches and rugged cliffs. The optimal conservation of its forests makes them a good representative of the average western Cantabrian mountain environment. No less important are the ethnographic and architectural riches of the area.
In its declaration as a Biosphere Reserve, UNESCO recognizes the work of the residents of the area in favour of sustainable development, which promotes growth while respecting the conservation of landscapes, ecosystems, species and genetic diversity. This is a landscape set in territories that have suffered the consequences of secular isolation over centuries, which it has been able to overcome thanks to making the most of opportunities to develop pioneering sustainability and rural tourism projects of international scope. All this, together with its natural and environmental values, scenery, economic activities and cultural and ethnographic heritage, has allowed the area to continue to progress and develop in an orderly and sustainable way. The scenic values of the area are undeniable, though what is especially notable is its historical background of social and economic action and the conservation of its heritage.
The unquestionable natural beauty of the Principality of Asturias is evident in its five listed Biosphere Reserves, and in the fact that a third of its territory –340,000 hectares– boasts some kind of conservation order.