The Île Sainte-Marguerite (pronounced [il sɛ̃t maʁɡ(ə)ʁit]) is the largest of the Lérins Islands, about half a mile off shore from the French Riviera town of Cannes.
Besides the Man in the Iron Mask, a mysterious prisoner whose identity remains unknown, Abd al-Qadir al-Jaza'iri (an Algerian rebel leader), Marquis Jouffroy d’Abbans (inventor of the steamboat) and Marshal Bazaine (the only successful escapee from the island) have all spent time there.
A fifteen-minute boat ride from Cannes, the Île de Sainte-Marguerite is low in profile and heavily wooded with umbrella pines and eucalyptus.
Both islands (with the Île Saint-Honorat) are looked after by the Office national des forêts, and are a popular tourist attraction of natural interest.
The historic Fort Royal now houses a youth hostel and a Museum of the Sea, featuring items recovered from ancient Roman and Saracen shipwrecks.