The design of Fort du Randouillet (1724-1734) has a very complicated design. It consists of a number of plateaus with gun casemates. However the eastern front is more classical with its ravelin. In the center of the fort you can see the Haxo-battery built around 1844 and named after its desginer. It consists of five gun casemates. On top you can see a mast of the cable railway linking the citadel with Fort de l'Infernet.