The main island is located about twenty kilometers from the continent. It can be reached by boat at the pier located in Fromentine. The island has two different sides:
- the east coast is sandy, green, similar to what you see on the Vendée coast; this is also the side with the capital Port-Joinville.
- the western coast, is a “côte sauvage” containing granite rock with coves and cliffs. The highest point is located between “le Vieux Château” and the “Cap des Degrés”; it is 31 meter high.