The Citadel  Avenue Roger Salengro

The Citadel, after having retaken Calais from the English, the kings of France were worried about losing it, because of its privileged geography. They decided to destroy the former medieval castle and in its place construct, in 1560 to 1571, a vast citadel better oriented to the new techniques of war. In spite of this fortification, archduke Albert of Austria, leading the army of the Netherlands, seized Calais on April 24, 1596. This Calais invasion continued until the treaty of Vervins, that gave the city back to France.
On the occasion of their visit, Louis XIII and cardinal Richelieu considered making Calais an immense walled city that could become a vast military harbour. But this project came to nothing and only an arsenal and two new bastions were built.
It was at the time of the visit of the Sun King that the restoration of the fortifications of the citadel and Fort Risban were handed to Vauban.