Fort du Lomont, Military fortification in Doubs, France

Fort du Lomont is a Séré de Rivières fort built between 1875 and 1878 by the Adrien Hallier company on the summit of the Lomont chain, within the communes of Chamesol, Montécheroux and Pierrefontaine-lès-Blamont. A 1.5 km enclosure rings a southern reduit and a northern battery, each with its own barracks. In the photograph, a roofless stone corridor shows two rows of arched openings, the lower ones blind, with brick edging around several arches.

Fort du Lomont was built between 1875 and 1878 by the Adrien Hallier company as a Séré de Rivières work within the eastern fortifications and the Lomont defensive group. From 1935 to 1939 it served as a regional mobilization centre, first held by a company of the 35th Infantry Regiment, then by the 21st Battalion of Chasseurs à Pied. In September 1939 the 159th Foot Artillery Regiment moved in; on 6 September 1944 the maquis took the fort, which became de Lattre de Tassigny's starting base for the Doubs offensive.

The fort functioned as a communication relay point between mountain fortifications, with signal systems connecting it to neighboring positions across the high ground.

The fort sits atop a mountain ridge and requires hiking to reach it, with the path and terrain varying in difficulty depending on the approach route. Visitors should bring appropriate footwear and weather gear due to exposure at the elevated location.

The northern section contains a substantial artillery battery that dominates the ridgeline and reveals the fort's strategic positioning. The powder magazine carved directly into the bedrock demonstrates the specialized engineering techniques used in late 19th-century military construction.