Mezquita de Almonaster la Real Monument · Almonaster la Real, Sierra de Huelva, Huelva 10th-century mosque built over a 5th-century Visigothic basilica, with a trapezoidal layout and a surviving mihrab; one of the best-preserved rural Islamic buildings in Spain. siglo X Photo: Luis Rogelio HM (CC BY-SA 2.0) What to see and do in Almonaster la Real