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.