Grande écluse de Fortification – Vauban Dam

The Vauban Dam, a large fortified sluice

From the Middle Ages to the 17^th century, a system of fortified covered bridges ensured the city’s defense on the vulnerable side where the Ill divides into four channels.

Advances in fortification rendered this system obsolete, so a little upstream from the old bridges a large fortified sluice was built spanning the full width of the Ill. The structure was named the Vauban Dam, after the engineer who designed the plans executed by his collaborator Jacques Tarade around 1685–1700.

Beneath each of the thirteen arches of the sluice, movable iron panels made it possible to control the flooding of the city’s southern front and, if necessary, make it impassable to assailants, who were further slowed by deterrent portcullises. Three arches were raised in 1784 to facilitate the flow of seasonal torrential waters.

A panoramic terrace open onto Strasbourg

Like the Covered Bridges, the Vauban Dam did not always have the stony appearance we know today, as it was once topped by an upper timber-framed level covered with a gabled roof. During another transformation in 1865, the structure was heightened by a vaulted storey in sandstone and brick, and covered with an earthen embankment to withstand modern artillery fire.

Since 1996, the sluice has lost all military functionality and has been transformed into a panoramic terrace illuminated at night and open to the public by day—a privileged vantage point from which the eye takes in both the Covered Bridges and Petite France, with Strasbourg as a backdrop.

• Tram B ou C - arrêt Musée d’art moderne

• Terrasse panoramique