Gressvik, Norway offers 3 beaches perfect for sunbathing, surfing, swimming, and more. Gressvik is known for its proximity to the scenic Hvaler archipelago and the historic Fredrikstad Fortress. The best time to travel to Gressvik, Norway, is during the summer months of June to August, when the average air temperature is around 15-20°C (59-68°F) and the water temperature is approximately 15°C (59°F). Sandee provides detailed maps, photos, and reviews from fellow beachgoers to help you Choose Your Beach™ and plan your perfect beach vacation!