Butrón Castle is one of the most beautiful and picturesque castles that have survived to this day. This Spanish castle was founded around the XI century by the Butron family. For over three hundred years, from the 16th century onwards, the castle was the scene of non-stop and bloody fights between two sides of Bizkaia's nobility. The lords of Butrón, sheltered in the castle, exerted their power in that area. But Butrón has not always been a castle. In the middle of the 13th century it was a tower-house and the Fifth Lord of Butrón transformed it into a castle in the 14th century.