Nagaoka, Japan offers 5 beaches perfect for sunbathing, surfing, swimming, and more. Helen's Bay is known for Crawfordsburn Country Park and its scenic coastal walks. The best time to travel to Nagaoka, Japan, is in late spring (May), when the average air temperature is around 18°C (64°F) and the water temperature is approximately 16°C (61°F). Sandee provides detailed maps, photos, and reviews from fellow beachgoers to help you Choose Your Beach™ and plan your perfect beach vacation!