Rantum, Germany offers 3 beaches perfect for sunbathing, surfing, swimming, and more. Rantum is known for its beautiful beaches and the Rantumbecken nature reserve. The best time to travel to Rantum, Germany, is from June to August, with average air temperatures around 18°C (64°F) and water temperatures around 17°C (63°F). Sandee provides detailed maps, photos, and reviews from fellow beachgoers to help you Choose Your Beach™ and plan your perfect beach vacation!