Declared a Biosphere Reserve by the UNESCO, and sheltered by Matxitxako Cape and Izaro island, it is one of the areas with the biggest landscape and ecological diversity in the Basque Country. Mundaka and Bermeo are the best viewpoints to admire the spectacular union between fresh and salt water that takes place in Urdaibai. During the winter, Urdaibai is also home to many rare migratory birds such as the fish eagle and the spoonbill. Its marshes, full of mud and reeds, constitute a habitat of extraordinary ecological and natural value. Located on the right bank of the estuary, Agustín Ibarrola’s Painted Wood of Oma is worth a visit.