Of triangular shape, It ends by three headlands: Grosse Pointe in the east is an abrupt cliff which plunges into Dominica Passage, Basse Pointe in the north of the island overlooking la Redonde, in front of which is located a series of sharpened rocks called les Quilles and Pointe des Colibris on the west, forming with the eastern headland of la Coche, the dangerous passage called Passe des Dames. The island is about 900 m (0.56 mi) from east to west and 1,200 m (0.75 mi) from north to south. The official size is 84 hectares (although some mistakes appear with a calculated 48 hectares) . Its highest mount, Morne Grosse Pointe hill culminates at 165 m (540 ft). It contain two coves: Anse du Grand Etang, a rocky inlet characterized by its large pond and Anse des Colibris, on the west side of the island.
Grand-Îlet Passage is formed by Basse Pointe headland and la Redonde.[3]
The xerophile forest of all the islands of the archipelago of les Saintes is also protected, in particular woodlands of Eugenia axillaris, an important species among the Lesser Antilles.
Grand Îlet is included in the area of the natural reserve of the islands of les Saintes.[6] It is a remarkable site of submarine observation, due to the presence of a diving sec in full swell. It is a submarine mountain which the base is at less 25 m (82 ft) and the top at less 5 m (16 ft) below sea level. The place abounds in an incredible variety of sponges, gorgonians, corals and fishes of the Antilles, attracting the divers.[7]
Conservatoire du littoral (2010), Dacota (ed.), La Guadeloupe entre terre et mer
Sylvestre, Richard (2010), Association génération découverte avec la participation du Parc national et la Région Guadeloupe (ed.), Sept trésors des Antilles, vol. tome 1