Sveti Petar, Croatia offers 1 beach perfect for sunbathing, surfing, swimming, and more. Sveti Petar, Primorje Gorski Kotar, Croatia, is known for its proximity to the stunning Plitvice Lakes National Park. The best time to travel to Sveti Petar, Croatia, is from June to September, with average air temperatures around 75°F (24°C) and water temperatures around 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!