Historically, Lille was known as one of the most often besieged cities in western Europe. It belonged at various times to the County of Flanders, the Kingdom of France, the State of Burgundy, the Holy Roman Empire and the Spanish Netherlands.
After besieging, conquering and occupying Lille in 1667, the French King Louis XIV (= the 14th) immediately decided to fortify the city with the intention of making it a permanent part of France.
The fortifications were designed and constructed by (three guesses) Sébastien Le Prestre, marquis de Vauban (1633-1707), who had also organized the successful siege of the city. Construction began immediately. The Citadel and the surrounding bastions, in the form of a five-pointed star, were completed by 1670.
Vauban was in his thirties at this time and was starting to develop new methods of conducting sieges and designing fortifications. His zigzag design ensured that no attackers could approach any wall of the Citadel without coming under fire from defenders on one of the other walls.
Today the Citadel is still used by the French Army and is not open to visitors. But the surrounding bastions are well preserved and have paths which are popular for walking, jogging and cycling.
Location, aerial view and photo of the Citadel of Lille on monumentum.fr.
My photos in this post are from 2013. I revised the text in 2018.
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