Île Saint-Lanne Gramont is an uninhabited island, the fourth largest island in the Kerguelen Islands, situated to the north of presqu'île de la Société de géographie, with an area of 45.8 km². It reaches 480 m at its highest point and is located at (48°55′25″S69°10′54″E). The island is elongated along a north-south axis, reaching a maximum length of 13 km and a maximum width of 3 km.