The river Aranzuelo is a tributary of the river Arandilla and this is the river Douro.
Important dataThis river is born in the Castilian-Spanish province of Burgos, specifically in the Ribera del Duero region. It has a route from birth in Doña Santos until it flows into the Arandilla River of about 44 km. History
Some Basque authors wonder why the name of Aranzuelo and not that of Arauzuelo. They consider that there is a very powerful reason to think that its primitive name was Arauzuelo. This leads to indicate, according to some researchers, that these populations would have given origin to the diminutive of the name of the river. Localities Tributaries
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