Porto Ercole, Italy offers 7 beaches perfect for sunbathing, surfing, swimming, and more. Porto Ercole is known for the Spanish Fortress and the picturesque harbor. The best time to travel to Porto Ercole, Italy, is from May to September, when the average air temperature is around 75°F (24°C) and the water temperature is approximately 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!