Flaten, Sweden offers 1 beach perfect for sunbathing, surfing, swimming, and more. Flaten is known for Flaten Nature Reserve and Flatenbadet, a popular beach area. The best time to travel to Flaten, Sweden, is during the summer months of June to August, when the average air temperature is around 20°C (68°F) and the water temperature in Flaten Lake is approximately 18°C (64°F). Sandee provides detailed maps, photos, and reviews from fellow beachgoers to help you Choose Your Beach™ and plan your perfect beach vacation!