Fort du Haut-Buc

Fort du Haut-Buc is a fortification located on the Saclay plateau at about 160 meters elevation with trapezoidal architecture and multiple defensive structures. The complex includes underground passages and was designed as a comprehensive defensive system.

The fortification was constructed between 1874 and 1880 as part of the Séré de Rivières defense system. It was designed to house approximately 820 soldiers and 56 artillery pieces.

This fortification represents French military engineering from the late 1800s, embodying the nation's response to the Franco-Prussian War. The design reflects the strategic thinking of that era.

The site is not open to public access as it serves as a training ground for law enforcement and maintains restricted military status. External views are possible, but the interior remains closed.

The fort had two bread ovens capable of baking 226 rations each daily to feed the garrison. A large underground reservoir of about 525 cubic meters stored water without requiring a well system.