Île Sainte-Marguerite is the largest of the Lérins Islands, located off the coast of Cannes, France. It is known for its natural beauty, featuring lush pine forests and clear blue waters. The island is a popular destination for visitors seeking outdoor activities like hiking, swimming, and picnicking. The island is also home to the historic Fort Royal, which dates back to the 17th century. This fort once served as a prison, famously holding the Man in the Iron Mask. Today, visitors can explore the fort and enjoy stunning views of the surrounding Mediterranean Sea.