South Bethany, United States offers 2 beaches perfect for sunbathing, surfing, swimming, and more. South Bethany is known for its tranquil beaches and proximity to the Delaware Seashore State Park. The best time to travel to South Bethany, United States, is from June to August, when the average air temperature is around 75-85°F and the water temperature is approximately 70-75°F. Sandee provides detailed maps, photos, and reviews from fellow beachgoers to help you Choose Your Beach™ and plan your perfect beach vacation!