Rumeli Kavagi, Turkey offers 1 beach perfect for sunbathing, surfing, swimming, and more. Rumeli Kavagi, Istanbul, Turkey, is known for its historic Rumeli Kavagi Fortress and scenic views of the Bosphorus Strait. The best time to travel to Rumeli Kavagi, Turkey, is from late May to early September, when the average air temperature is around 25°C (77°F) and the water temperature is approximately 22°C (72°F). Sandee provides detailed maps, photos, and reviews from fellow beachgoers to help you Choose Your Beach™ and plan your perfect beach vacation!