Fortified region of Belfort

The fortified region of Belfort (place fortifiée de Belfort) formed the first line of defense in the Séré de Rivières system of fortifications in the Belfort Gap. Located in northeastern France between Épinal and Besançon, the primary line was built in the late 19th century to deal with advances in artillery that had made older defensive systems obsolete.

Belfort has been a fortified place since the Middle Ages, when a castle was built in 1226. After withstanding seven sieges, the medieval fortifications were modernized between 1637 and 1648 by the Comte de la Suze. Vauban added hornworks and a barracks to the castle, and enclosed the city in a new wall according to Vauban's "second system." These fortifications successfully resisted a siege in 1815.

As armies made greater use of artillery, it became necessary to extend city defenses to keep the enemy sufficiently distant to prevent bombardment of the city from neighboring high ground. The first ring of forts was built at the direction of General François Nicolas Benoît, Baron Haxo, beginning in 1817. The forts of La Miotte, La Justice and the Le Vallon camp were built, and the city walls were improved. Further increases in the range of artillery caused the construction of more forts to the south and east, resulting in Fort Bellevue, Fort des Barres and the Forts des Perches. These forts formed a rough ring about 1200m to 1500m from the town walls. They successfully resisted attack in 1870–71.

Shortly after France's traumatic defeat in the Franco-Prussian War of 1870–71, Belfort, an important road and railway node, and the frontier cities of Épinal, Toul and Verdun were chosen to constitute the first line of defense against an enemy incursion from the annexed former French provinces of Alsace and Lorraine. The fortifications were part of an extensive network of new forts proposed and carried out by Raymond Adolphe Séré de Rivières. The fortified region of Belfort runs between Fort de Giromagny, part of the High Moselle line, and Fort Lachaux of the defensive network of Lomont. The object of the program was to transform the Belfort area into a fortified camp.

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