Réunion Island, a French department in the Indian Ocean, is known for its volcanic, rainforested interior, coral reefs and beaches. Its most iconic landmark is Piton de la Fournaise, a climbable active volcano standing 2,632m (8,635 ft.). Piton des Neiges, a massive extinct volcano, and Réunion’s 3 calderas (natural amphitheaters formed by collapsed volcanoes), are also climbing destinations.