Fort de l'Est, Military fortress in Saint-Denis, France

Fort de l'Est is a four-sided military strong point built between 1841 and 1843 in Saint-Denis, its northeast bastion cut away in 1963 for the A1 autoroute, from which its dark stone wall with four narrow vertical slits is visible. The glacis in front is partly taken up by community gardens.

The fort was built between 1841 and 1843 under Prime Minister Adolphe Thiers as part of a 17-fortress ring protecting Paris from invasion. It saw combat during the 1870-1871 war when defenders fired at enemy positions from its walls.

The fort remains an active army site: reserve units train there and the headquarters of the National Association of Reserve Warrant Officers is housed within it, alongside Foreign Legion units deployed under Operation Vigipirate. Its glacis is partly taken up by community gardens, which photographer Patrick Zachmann documented in 1994.

The fort remains an active French Army site, so the interior is not open to visitors; it is seen from the A1 autoroute and from the rue du Fort-de-l'Est. The northeast bastion was cut away in 1963 for the motorway, leaving the wall facing the Lycée Suger built in 1994. Community gardens occupy part of the glacis.

The fort's chaplain, Jules Bonhomme, published a popular memoir in 1872 titled Souvenirs du Fort de l'Est, près Saint-Denis, which made the garrison known to a wide readership. The military archives on World War I insubordination in the French Army are kept here, along with unclassified files from the former garrison library.