Agüera River

The Agüera River, also called Riomayor,[2] is a river in northern Spain, on the Cantabrian coast, which runs through Cantabria and Biscay and flows into the Cantabrian Sea.The Agüera rises in the foothills of the Burgueño, between the municipalities of Valle de Villaverde and Arcentales and flows into the Oriñón estuary, between Guriezo and Castro-Urdiales. Its main tributaries are the Remendón, Andino and Rioseco rivers. It has an annual flow of 112 hm³ and a length of 29 km.

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