Málaga is an important tourist destination, known as "the capital of the Costa del Sol". An estimated 6 million tourists visit the city each year, who usually visit the birthplace of Pablo Picasso.
San Sebastian is a superb beach location just west of the Pyrenees with excellent food (tapas). It should be on everyone's itinerary.
The Canary Islands are politically part of Spain, but closer to Morocco. The islands are mainly volcanic with a very pleasant spring-like climate year-round.
Santiago de Compostela is the capital of Galicia and the end point of the pilgrimage "Camini de Santiago" and the apostel James should be buried here. The journey here is different from other journeys since people like to either walk or bike.
Seville is the capital of the Andalusian region that also includes Malaga and Granada. It is very Spanish here with historical buildings, Flamenco Music & Dance, horses, Paella and Sangria. Note that it can be really hot (40°C and more) in Summer...
Cordoba has a beautiful old city center with a lot of charm. The main attraction however is La Mesquita, a cathedral that started as a mosque. Cordoba is one of the hottest cities in Europa in Summer.
Madrid, capital of Spain and home of the royal family. The city center with great architecture is amazingly small, with nice places to enjoy local food and wines and very walkable.
Ronda, Andalusia, is known for its cliffside location and a deep canyon that divides the town. Both sides are connected by an ancient viaduct. Another point of interest is the, now not used, arena for bull fighting.