Glenduan, New Zealand offers 1 beach perfect for sunbathing, surfing, swimming, and more. Glenduan, Nelson, New Zealand, is known for the Boulder Bank, a natural geological formation and popular walking destination. The best time to travel to Glenduan, New Zealand, is during the summer months of December to February, when the average air temperature is around 20°C (68°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!