A project initiated by Vauban
Related to the British invasion of 1761
In the past, Belle-Île was a strategic military position, facing the southern Breton coasts and the mouth of the Loire River. Its agricultural production and freshwater resources made it a privileged home base for the navy. The building of the citadel, in the 16th and 17th centuries, redesigned by Vauban, engineer of the fortifications of Louis XIV, at the end of the 17th century, testifies to this. Vauban had initially planned the construction of a fortified enclosure on the heights of Palais to support the citadel. He had even drawn the outlines, but due to a lack of funds, the work could not be carried out.
When the British invaded in 1761, they installed their cannons in the place where the city wall should have been built. Its construction was then considered essential to ensure the security of Belle-Île.