Castell de Rey, Spain offers 1 beach perfect for sunbathing, surfing, swimming, and more. Castell de Rey, Andalusia, Spain, is known for the Alhambra Palace. The best time to travel to Castell de Rey, Spain, is in late spring or early fall when the average air temperature is around 70°F (21°C) and the water temperature is approximately 68°F (20°C). Sandee provides detailed maps, photos, and reviews from fellow beachgoers to help you Choose Your Beach™ and plan your perfect beach vacation!