At the northern end of the windmill ridge, the Castillo de la Muela is one of the most dramatically sited castles in central Spain. Built on the foundations of a Roman watchtower, expanded by the Moors, and reconstructed by the Knights of the Order of Saint John (the Knights Hospitaller) after the Reconquista, it has crenellated walls, three round towers, and a vaulted Romanesque chapel inside.
The view from the ramparts over the brown La Mancha plain — flat for fifty kilometres in every direction — is unforgettable. Open most days; a small entry fee includes the chapel and the small museum of medieval armour. Combine with a walk along the ridge between the mills.