Built between 1875 and 1878, Fort du Lomont was used for military purposes until the early 21st century. It is located on the Lomont massif, in the municipality of Vermondans between Pont-de-Roide, Blamont and Saint-Hippolyte, in the Doubs department. This fortification is one of the key structures in the Lomont defensive hub , along with the Mont-Vaudois, Lachaux, Mont-Bart and Les Roches forts.

Its strategic position meant that, if necessary, it could block the passage between Montbéliard and the Swiss border. With views over the Lomont region, the Vosges peaks and the snowy peaks of the Bernese Alps, the fort had a triple caponier which defended three ditches. Its armament was reinforced by two ancillary batteries. t was armed until 1915 and was reinforced during the Second World War. Four peace barracks were later built. These fortifications extend over an area of 12 hectares, on a 28-hectare site. Demilitarisation took place in 2008. It was subsequently acquired by the Communauté de communes des Balcons du Lomont and, since 2017, by the Communauté d’Agglomération du Pays de Montbéliard.

The Fortissimo Association organises festive markets, creative workshops, garage sales, concerts, exhibitions, etc. at the fort, all with a view to local and sustainable development.