Fort des Rousses, Military fort in Les Rousses, France

Fort des Rousses is a large military fortress at 1150 meters elevation featuring extensive vaulted chambers and underground passages throughout its structure. The subterranean design maintains consistent temperature and humidity levels year-round.

Colonel Christin fortified the Rousses position in 1815 with five redoubts, facing a feared Austrian invasion through Swiss neutrality. A 93-hectare site southwest of the village was bought in 1841, and work on the fort began in 1843, lasting about twenty years; the entrance porch is inscribed 1848, though completion is dated to 1862-1863. Artillery arrived only in 1868, when the armament was set at 88 defence and 27 security pieces for a garrison of 3,500, and the fort was renamed Fort Général Henry Martin in 1984.

The fort now functions as a storage facility for Comté cheese, shaping daily life in this mountain region. You can walk through the vast chambers where thousands of cheese wheels rest in the cool underground environment.

The fort stands at 1,150 m on a wooded rise southwest of Les Rousses, with two entrances: the Porte de France to the north and the Porte de Suisse to the east, the latter behind a Poncelet drawbridge. Inside, a flat, easy path crosses the 21-hectare enclosure, and the vaulted cellars hold a constant 8 °C, so bring warm clothing.

In 1997 this military installation was transformed into a cheese storage facility, taking advantage of the existing underground structure's natural properties. This conversion demonstrates how historic buildings can serve entirely new purposes.