Opatija, Croatia offers 8 beaches perfect for sunbathing, surfing, swimming, and more. Tanjungsari, Central Java, Indonesia, is known for its proximity to the Dieng Plateau, a popular tourist destination featuring ancient Hindu temples and stunning volcanic landscapes. The best time to travel to Opatija, Croatia, is from June to September, when the average air temperature is around 75°F (24°C) and the sea temperature is approximately 73°F (23°C). Sandee provides detailed maps, photos, and reviews from fellow beachgoers to help you Choose Your Beach™ and plan your perfect beach vacation!