The waters of the Cantabrian Sea have sculpted the rocks of the Catedrales Beach with unique forms—arches within arches, columns, vaults, and sand corridors between slate walls, making this beach a one-of-a-kind natural monument. These structures are only visible when the tide is low, and it's during this time that we can enjoy about 1,300 meters of sandy shoreline. It's a protected area within the Natura 2000 Network.