San Juan Piedras Negras, Mexico offers 1 beach perfect for sunbathing, surfing, swimming, and more. San Juan Piedras Negras is known for its proximity to the ancient Zapotec ruins of Monte Alban. The best time to travel to San Juan Piedras Negras, Mexico, is from November to April, with average air temperatures around 70-85°F and water temperatures near 75-80°F. Sandee provides detailed maps, photos, and reviews from fellow beachgoers to help you Choose Your Beach™ and plan your perfect beach vacation!