Grande Ile Coquillage, British Indian Ocean Territory offers 1 beach perfect for sunbathing, surfing, swimming, and more. Grande Ile Coquillage is known for its pristine beaches and vibrant coral reefs in the British Indian Ocean Territory. The best time to travel to Grande Ile Coquillage in the British Indian Ocean Territory is from May to October, with average air temperatures around 27°C (81°F) and water temperatures near 28°C (82°F). Sandee provides detailed maps, photos, and reviews from fellow beachgoers to help you Choose Your Beach™ and plan your perfect beach vacation!