Frederikssund, Denmark offers 2 beaches perfect for sunbathing, surfing, swimming, and more. Frederikssund is known for the Viking Ship Museum and the annual Viking Festival. The best time to travel to Frederikssund, Denmark, is during the summer months of June to August, when the average air temperature is around 17°C (63°F) and the water temperature 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!