Castelo do Neiva, Portugal offers 2 beaches perfect for sunbathing, surfing, swimming, and more. Castelo do Neiva is known for its beautiful beaches and scenic coastal views. The best time to travel to Castelo do Neiva, Portugal, is from late spring to early autumn (May to September), when the average air temperature ranges from 18°C to 25°C (64°F to 77°F) and the average sea temperature is around 17°C to 20°C (63°F to 68°F). Sandee provides detailed maps, photos, and reviews from fellow beachgoers to help you Choose Your Beach™ and plan your perfect beach vacation!