West Union, United States offers 1 beach perfect for sunbathing, surfing, swimming, and more. West Union, Ohio, United States, is known for the Serpent Mound, a prehistoric effigy mound shaped like a serpent. The best time to travel to West Union, United States, is in late spring or early fall when the average air temperature is around 60-75°F, though water temperatures in nearby lakes and rivers can be cooler, averaging 50-65°F. Sandee provides detailed maps, photos, and reviews from fellow beachgoers to help you Choose Your Beach™ and plan your perfect beach vacation!