Dong Hai, Vietnam offers 1 beach perfect for sunbathing, surfing, swimming, and more. Dong Hai, Tra Vinh, Vietnam, is known for its serene rural landscapes and traditional Khmer culture. The best time to travel to Dong Hai, Vietnam, is from December to April, with average air temperatures around 25-30°C (77-86°F) and water temperatures around 24-28°C (75-82°F). Sandee provides detailed maps, photos, and reviews from fellow beachgoers to help you Choose Your Beach™ and plan your perfect beach vacation!