Sandy Cay National Park, British Virgin Islands offers 1 beach perfect for sunbathing, surfing, swimming, and more. Sandy Cay Island, British Virgin Islands, is known for its pristine beaches and vibrant marine life within Sandy Cay National Park. The best time to visit Sandy Cay National Park in the British Virgin Islands is from December to April, with average air temperatures around 77-82°F (25-28°C) and water temperatures about 79-82°F (26-28°C). Sandee provides detailed maps, photos, and reviews from fellow beachgoers to help you Choose Your Beach™ and plan your perfect beach vacation!