Marina Bay, Antigua and Barbuda offers 2 beaches perfect for sunbathing, surfing, swimming, and more. Saint John, Antigua and Barbuda is known for Nelson's Dockyard, a UNESCO World Heritage site. The best time to travel to Marina Bay, Antigua and Barbuda, is from December to April, with average air temperatures around 77-82°F (25-28°C) and water temperatures around 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!