Juan de Nova Island is a 4.4 km² low, flat, tropical island in the narrowest part of the Mozambique Channel, about one-third of the way between Madagascar and Mozambique. Anchorage is possible off the northeast of the island which also has a 1,300-metre-long airstrip. Administratively, the island is one of the Scattered islands in the Indian Ocean, a district of the French Southern and Antarctic Lands.
Juan de Nova, about six kilometres long and 1.6 km at its widest, is a nature reserve surrounded by reefs which enclose an area (not a true lagoon like in an atoll) of roughly 40 km². Forests, mainly of Casuarinaceae, cover about half the island. Large numbers of terns (Sterna fuscata) breed there from November to March. Turtles nest in the beaches around the island.