Séré de Rivières system
Ouvrage Les Sarts is a "petit ouvrage" of the Maginot Line, built as part of the "New Fronts" program to address shortcomings in the Line's coverage of the border with Belgium. Like the other three "ouvrages" near Maubeuge, it is built on an old Séré de Rivières system fortification, near the town of Marieux.