Casma, Peru offers 5 beaches perfect for sunbathing, surfing, swimming, and more. Casma is known for the Sechin archaeological site and the beautiful beaches of Tortugas. The best time to travel to Casma, Peru, is from December to March, with average air temperatures around 77°F (25°C) and water temperatures near 73°F (23°C). Sandee provides detailed maps, photos, and reviews from fellow beachgoers to help you Choose Your Beach™ and plan your perfect beach vacation!