If you're in Madrid this summer make sure to catch the special Picasso exhibit (Picasso tradición y vanguardia) at the Reina Sofía The exhibit commemorate the Guernica's return to Spain from the Museum of Modern Art New York 25 years ago. The exhibit runs till early September. I recently visited it with my team from work, we had a private guide and it was really worth it. I'd recommend at least getting an audio guide to really get the most out of it.
