Museo Nacional Centro de Arte Reina Sof &7;a --- The Master's Art Palace also has free visits to the Sofia Queen's Art Center Museum, named after the Spanish Queen, one of the three major Spanish art galleries. Free Open Days: 19:00-21:00 on Monday, Wednesday and Saturday, 13:00-19:00 on Sunday; 19:00-21:00 on April 18, May 18, October 12 and December 6, free visits, free tickets are also beautiful.