Sierras del Mar, Uruguay offers 1 beach perfect for sunbathing, surfing, swimming, and more. Sierras del Mar is known for its scenic landscapes and proximity to the renowned Piriapolis beach resort. The best time to travel to Sierras del Mar, Uruguay, is from December to February, with average air temperatures around 75°F (24°C) and water temperatures near 72°F (22°C). Sandee provides detailed maps, photos, and reviews from fellow beachgoers to help you Choose Your Beach™ and plan your perfect beach vacation!