Europa Island , volcanic island, c.11 sq mi (28 sq km), between Madagascar and Mozambique in the Mozambique Channel, W Indian Ocean. A possession of France since 1897, Europa is flat, low-lying, and heavily wooded. Classified as a wildlife sanctuary, it is the site of a small military garrison. a weather station, and a tiny airstrip. Administered by a commissioner based in Réunion, the island is also claimed by Madagascar.