The Urdaibai Biosphere Reserve covers 22,000 hectares and is made up of a mosaic of cliffs, mountains, beaches, rivers and groundwater , which offer a spectacular landscape full of animal and human life .
In order to harmonize the conservation of biological diversity, heritage and cultural expressions, on the one hand, and economic development and the relationship between people and their environment, in 1984 UNESCO included Urdaibai in its Man and the Biosphere programme , through its declaration as a Biosphere Reserve.