Lanark, United States offers 1 beach perfect for sunbathing, surfing, swimming, and more. Lanark is not typically known for travel and beach tourism. The best time to travel to Lanark, United States, is in late spring (May), when the average air temperature is around 65°F (18°C) and water temperature is approximately 55°F (13°C). Sandee provides detailed maps, photos, and reviews from fellow beachgoers to help you Choose Your Beach™ and plan your perfect beach vacation!