A stronghold, built by Vauban.

Following the Treaty of the Pyrenees in 1659, Vauban created Mont Louis in 1679 to secure the border with Spain.  The stronghold (and in particular the exceptional workings of the  'galley slave well', with its enormous wheel), is a great example of military architecture from the 17th century, which has retained its principal vocation, as the citadel is still occupied by the army today.

Therefore, The National Centre of Commando Training, which occupies the upper part of the citadel, is a reminder that Mont-Louis has always been a military stronghold.

Mont-Louis is listed in the UNESCO Worldwide Heritage.

Guided tour of the town and the 'galley slave well', which provides the citadel's water supply, and whose impressive wheel from the 17th century is in an excellent condition of conservation.