
The Estuary Lock : Vauban's work
Fort Médoc is part of the “Verrou de l’estuaire”, a defensive system unique in France, also known as the defensive triptych. This system is made up of the Citadelle de Blaye, the Fort Pâté (an island in the middle of the estuary) and Fort Médoc. These works, dating from the late 17th century, were designed to lock the entrance to the Gironde estuary and protect Bordeaux, located just 50 kilometres upstream.
Vauban, accompanied by his engineer Ferry, achieved a technical feat in erecting these fortifications. At Blaye, he redesigned the medieval fortress into a modern stronghold, while at Cussac, Fort Médoc, was built on marshy ground, where Vauban opted for earth defences and palisades. Finally, on Île Pâté, another challenge was met: the construction of an oval gun tower, Fort Pâté, right in the middle of the estuary, allowing fire to cross with the other fortifications.