Medina Azahara must have been a wonder of the age: a palace city, splendid rooms with precious ornaments with no equal at the time, at least in Europe. So, expectations can be high for an unprepared visitor, but what do you get to see? I nice museum with small finds and scraps of ornaments and explanations about the palace city. When you get on the bus to the excavations (beware: they do run only about every 20 minutes and lines can be long so you may miss one) it is not much more then empty ground walls and a few very heavily restored arches. They say it is only 10 percent of the original palace city, but it seems to be the central area and there is no reason to assume further excavations would be better preserved.
While this is an interesting visit it is certainly not a must compared to the center of Cordoba and its nice Archeological Museum. This seems to be very much inscribed for what it was and represented at the time rather than for what is left today. As an extension of Cordoba, it would add a small facet to this WHS but if we are reasonable, on its own it lacks any OUV and should not have been inscribed.