Located in the low part, under the Citadel, the city, or plaintiff, was initially planned by Vauban to host traders, craftsmen, middle-class persons, and a barrack.
Its defenses (ramparts, bastions et half-moons) were built in the same time of the Citadel. However, its urbanization, the living houses were built about fifty years after the inauguration of the place.
In the South, the Porte de France and its drawbridge are the only access to Mont-Louis.
The post of granting (former tax on the import of goods), settled in one of the half-monns, controlled the entrance at the hall of the town.
Drilled in the rampart, this passage in tunnel was secured by a drawbridge, three doors, a harrow and two staff rooms.
Like her military neighbor, the city is surrounded by ramparts and flanked by three bastions: the bastion of Perche, the bastion Saint-Pierre (renamed bastion Gilles) et the bastion of Têt. A dry ditch ends to surround the ramparts, several meters thick.
Throughout, hung on at the top of the ramparts, bartizans (small towers at the angle) allow to watch in any direction.
This military fortification system allowed the city of Mont-Louis to be never besieged. The only real threat engendered a battle at 3km from the town, at Col de la Perche in 1793 when the Spanish army intent was repelled even before having led their assault.
From now, a patrimonial signalling system on panels allows to roam in town to discover its history and architecture.