The Île Sainte-Marguerite island is most famous for its fortress prison (the Fort Royal), in which the so-called Man in the Iron Mask was held in the 17th century.
The island is first known to have been inhabited during Roman times, when it was known by the name Lero. In 1612, ownership of the island passed from the monks of Saint-Honorat to Claude de Lorraine, Duke of Chevreuse. Shortly after, construction of a fort on the island (to become the Fort Royal) began. In 1635, the island was captured by the Spanish and recaptured by the French two years later.
Towards the end of the 17th century, the Fort Royal became home to a barracks and state prison. During the 18th century, the present-day village of Sainte-Marguerite developed, thriving on the spending power of the soldiers stationed on the island.
The Fort Royal was home to a number of famous prisoners until its closure in the 20th century. As well as 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.
References:The Clementinum is a historic complex of buildings in Prague. Until recently the complex hosted the National, University and Technical libraries, the City Library also being located nearby on Mariánské Náměstí. The Technical library and the Municipal library have moved to the Prague National Technical Library at Technická 6 since 2009. It is currently in use as the National Library of the Czech Republic.
Its history dates from the existence of a chapel dedicated to Saint Clement in the 11th century. A Dominican monastery was founded in the medieval period, which was transformed in 1556 to a Jesuit college. In 1622 the Jesuits transferred the library of Charles University to the Klementinum, and the college was merged with the University in 1654. The Jesuits remained until 1773, when the Klementinum was established as an observatory, library, and university by the Empress Maria Theresa of Austria.