: Construction finally began in 1801 under Napoleon Bonaparte but was suspended in 1809 due to technical struggles and constant British attacks.
: It measures approximately 68 meters (223 ft) long and 31 meters (102 ft) wide , with stone walls rising 20 meters (66 ft) high. Layout : Fort Boyard Original
: In the 17th century, the range of artillery was insufficient to cover the gap between existing fortifications on the islands of Aix and Oléron . A fort midway between them was essential to protect the port and royal arsenal at Rochefort from British naval incursions. : Construction finally began in 1801 under Napoleon
: Designed as a shooting platform with a prominent watchtower at the highest point. A fort midway between them was essential to
As of 2025, significant restoration projects are ongoing to protect its foundations from erosion, with plans to potentially allow public access by 2028.