7. Albarracín, Spain Albarracín is a small town in the hills of east-central Spain, above a curve of the Guadalaviar River. Towering medieval walls, the Murallas de Albarracín, dominate the adjacent hillside. At their crest is 10th-century Andador Tower. The ruins of an alcázar, or Moorish castle, stand on a clifftop in the old town. The 16th-century Catedral del Salvador features a bell tower built on the remains of a Romanesque temple.