Located in the municipality of Plougonvelin, in Finistère, Fort Bertheaume was built in the late seventeenth century by Vauban at the request of Louis XIV. Top thirty-seven meters, it takes place on a rocky island located thirty meters from the shore.
Originally intended to protect the harbor of Brest, it is being worked on improvements to the twentieth century, including the addition of barracks, powder magazines or a wall. military used until 1944, the site was bought by the town in the 1990s and regularly hosts exhibitions and sounds and lights tracing the history of the places.
The thrill seekers can also enjoy zip lines and a climbing route.