Cuenca is much more than a beautiful historical center and the Enchanted City. It is also nature in its purest form. With very different surroundings than elsewhere in Spain, the road going from Cuenca to the Enchanted City is impressive. Among other things, the source of the Cuervo river is very close by, another wonderful place.
I recommend visiting Cuenca and the Enchanted City and then sleep in one of the fantastic holiday cottages in the villages around. In this way you can go on one of the routes in the "sierra" (mountainous region), it will be always worth it. Moreover the area is rather well indicated.