Adding another vote for the Alhambra. Highlight of our trip from over 20 years ago and eager to get back someday. There is a Parador there that allows you to spend the night. I spent a evening after hours walking the gardens by myself, with only the cute feral cats for company.

OK guys, you sold me on adding Granada & dropping Gibraltar. Tangier is still in however. Old men like their bucket lists...& conquests.
Re Toledo, Segovia & Cordoba day trips, should I book tours or are the cities small enough for a self tour?
Thanks again for all the help.

No need for a tour. Just get a decent guidebook or two.

Agree you can do Cordoba and Toledo easy with a good guide book. I really like Rick Steves' books. He doesn't just give you a list of things to see, but rates them as to what is extraordinary and what is just ok. We did take a little trolly/bus tour thing around Toledo. They are silly looking, but sometimes do the trick.