Real Sitio de San Ildefonso, Spain offers 2 beaches perfect for sunbathing, surfing, swimming, and more. Real Sitio de San Ildefonso is known for the Royal Palace of La Granja de San Ildefonso and its stunning gardens. The best time to visit Real Sitio de San Ildefonso, Spain, is during late spring to early autumn (May to September) when the average air temperature ranges from 15°C to 25°C, and there are no significant bodies of water for swimming. Sandee provides detailed maps, photos, and reviews from fellow beachgoers to help you Choose Your Beach™ and plan your perfect beach vacation!