I took a Spanish cultural class in Spain for 3 weeks in college. As mentioned above, Seville, Toledo, Segovia, and Madrid were fantastic. We also went to Granada to see the Alhambra....so worth it! We also spent time in Cadiz then took a hydroplane across the Strait of Gibraltar to Morocco. You can't go wrong with any of these options. I'm going again next spring/summer so any other information you find would be welcomed by me as well!