Don't Miss: Fort Bayard

The stuff of cinema, Fort Boyard is a 20m-high iceberg of a fortress island lording over the ocean midway between Île d'Aix and Île d'Oléron. It was dreamt up in the 1700s to defend the Bay of Rochefort against the English, but construction of the extraordinary 'stone ship' only began a century later. It then took 19th-century builders 62 years to complete: the first building materials were hauled out to sea in 1802 and the fort was finally completed under Napoléon III (1851–70).

At the end of the Second Empire, Fort Boyard became a prison for Prussian soldiers. Since 1990 the dramatic construction has been the TV studio and film location of the French TV game show Fort Boyard. Closed to visitors today, the unique fort is best admired on a boat trip or, in summer, close-up aboard a sea kayak with Antioche Kayak, kayak and stand-up paddle guides based 30km south of La Rochelle in Fouras.