Tower of los Caballos (Bolnuevo) Monument · Mazarrón, Bajo Guadalentín, Murcia Coastal defence tower of the 15th and 16th centuries built to watch the coast against Barbary pirate raids, declared a Bien de Interés Cultural and today housing an interpretation centre. Photo: Ellen Adam (CC BY-SA 4.0) What to see and do in Mazarrón