Ouvrage de la Salmagne is a petit ouvrage of the Maginot Line, constructed between 1934 and 1938 as part of the 'New Fronts' program to strengthen France's defensive network along the Belgian border. Located near the town of Bersillies in northern France, it was built atop the foundations of an earlier Séré de Rivières system fortification, integrating modern concrete and steel construction with the existing masonry structures. The ouvrage forms part of a defensive cluster near Maubeuge, alongside nearby ouvrages such as Bersillies.
Designed to house a small garrison, La Salmagne features deep underground galleries and reinforced concrete casemates typical of Maginot Line engineering. During the Battle of France in 1940, it played a role in the Siege of Maubeuge, contributing to the region's layered defense strategy. The site's preserved condition today offers insight into interwar French military architecture and the evolution of fixed fortifications.
The ouvrage is now open to the public, allowing visitors to explore its preserved tunnels, combat blocks, and historical exhibits. Its location in the rolling countryside of Nord-Pas-de-Calais makes it a notable destination for military history enthusiasts and those interested in the Maginot Line's legacy.