Please help this novice traveler. I plan to see Prado, Sofia, Palacio Real, Monasterio de las Descalzas Reales and Thyssen. I am interested in spending only a couple of hours at each place since I am not an art lover. I see Sofia is free on the 12th of October. I understand Prado is free at certain times. Am unclear when it is free and how much admission would be if I paid.Do any others have free times? Going next week and we are able to get museums when they open if needed to avoid rush. We don't like to plan to exaclty the times. Are there group tickets? Thank you very much.