Fort Boyard is a fort located in the Bay of Biscay between the islands of Île d'Aix and Île d'Oléron off the west coast of France. Construction began in the 17th century under King Louis XIV but faced many challenges due to its location in a sandbank. The fort was later completed in the 19th century under Napoleon and protected the arsenal at Rochefort until being abandoned in the late 19th century. It is now the site of a popular French television game show.