Put up near the Hagerue's gate and Amiens' gate, guess who built this master-piece? Louis XIV's famous architect, Vauban, of course! Began in 1688, the citadel was completed 3 years later.
In those pentagonal fortifications surrounded by moats, we had 5 bastions: bastion of the King, bastion of the Dauphin, bastion of Orléans and Anjou, bastion of the Queen. Two gates, the porte Royale and the porte de Secours, were built then.
The citadel had to protect Arras city from Spanish troops, but we soon gave it the nickname of "beautiful useless", la belle Inutile...