Timeline

Heritage classified

Key figures

Origin and history

The Saint-Amand de Verdun lock bridge, built between 1680 and 1685, is a key element of the defensive system designed by Vauban to protect the city from the south. It allowed, along with two other lock bridges now missing, to flood an area of 14 km upstream under 2 to 2.5 m of water, making any attack impossible. This mechanism, tested for the first time in 1687 before Louis XIV, was used only five more times in history.

Designed by King Peirault's engineer based on Vauban's plans, the lock bridge marks the junction between the Augustinian Canal and the Saint-Vanne Canal. Its originality lies in the integral preservation of its manoeuvring building and its original mechanism, a rarity in France. Ranked a Historic Monument in 1978, it benefited from major restorations between 2009 and 2011, notably on its structure and roof.

Architecturally, this 40 m long and 15 m wide masonry bridge consists of five vaults reinforced by triangular beaks. Its apron, divided between a 6 m roadway and a 9 m manoeuvring building, operated wooden beams via winches. These developments reflect the ingenuity of the Vauban fortifications, combining hydraulic functionality and military strategy.

A few decades after its construction, the engineer Louis de Cormontaigne modified the locks, adapting the work to technical developments. Today, the Saint-Amand lock bridge remains the only one of the three original bridges to remain in its entirety, bearing witness to Verdun's military and hydraulic legacy under the Old Regime.

External links