Dunkirk Basse Ville
With the new harbour and naval arsenal constructed by Louis XIV, the population of Dunkirk grew significantly in the second half of the 17th century. The medieval walls of the town were demolished to make room for more houses within the fortress. However, the town still became overcrowded, with no room for expansion due to the ring of fortifications.
In the 1690s it was decided was to build a Basse Ville (lower town). Although called the lower town, this was a purely figurative term borrowed from other places where the inner fortress stood above the suburbs. In the case of Dunkirk, the land was flat and offered no change in altitude. Instead, the Basse Ville was new a suburb on the south side of the town, with its own fortifications.
Another reason for the construction of the Basse Ville, also known as the Faubourg des Matelots (sailors' quarter) was to separate the newly arrived workers employed in the naval yard from the inhabitants of the town. It was felt that limiting the contact between these two groups of the population was necessary in order to prevent social unrest.
As for the fortifications, the Basse Ville was essentially a large crownwork extending south from the Porte Royale. The Basse Ville sat in the angle between two diverging canals, which formed its left and right flanks. The flanks themselves were not protected by ramparts, since the canals made effective barriers and in any case the left flank faced towards the town.
The right flank of the Basse Ville was covered by an outlying work, a small square redoubt that stood a short distance to the west. Called the Redoute du Marais, it was surrounded by a flooded ditch, probably mounted several guns and housed a garrison of a dozen men.
On the south side the Basse Ville was protected by two half-bastions and a full bastion, fronted by a flooded ditch and a covered way. The defences of the Basse Ville were less comprehensive than the other elements of the fortress, as demonstrated for instance by the lack of outworks. The reason for this is probably that a huge amount of money had been spent on creating the fortress and there was a reluctance to commit more resources to what had already been an expensive project. In addition, the Basse Ville's fortifications were themselves an outwork, rather than an important part of the defensive system.
In 1706 during the War of the Spanish Succession, the Allied army was threatening Dunkirk. In response, Vauban built an "entrenched camp" at Dunkirk. Extending south from the Basse Ville, this was an area of countryside where a large defensive force could camp, protected by a simple earthen rampart and ditch.