Ouvrage Janus - Fort Du Janus

Fort Du Janus

The location was known from the end of the 18th century as the Château Jouan, occupied by a Vauban-era round tower. In 1883 a Séré de Rivières system fortification was begun on the massif, called the Fort du Janus. Work continued until 1889 with a blockhouse in top of the position and a rock-cut battery in the face of the mountain, which housed four 95mm naval guns. In 1891-92 the blockhouse was expanded to two levels for a barracks, and from 1898 to 1906 a subterranean barracks was excavated. The whole was surrounded by a perimeter wall. The fort was armed with six guns on the ramparts in addition to the four naval guns in their unique casemate, which was added between 1898 and 1906. The garrison was 120 men. The perimeter was laid out with re-entrant angles to sweep the walls with fields of fire.

The underground component comprised three large chambers, a cistern with a capacity of 100 cubic meters of water, a kitchen, a small magazine and a connection to the 95mm gun casemate. The gun positions were separated by prominent buttresses to prevent fragments from affecting the entire battery, and each gun was provided with an exhaust hood for gun fumes. The 95mm battery provided flanking fire to the Gondran line on the Montgenèvre massif.