Belle Ile

Copy of 1704 Model of the citadel
A beautiful isle off the Brittany coast, the main port of Palais was fortified by Vauban in the late 1600s as well as potential landing sites.  Enemy possession of the island could help supply an enemy fleet with drinking water and food and provide a base for raiding the French coast and harassing French commerce.  The island had been fortified for centuries, most recently by Nicholas Fouquet, the finance minister, who planned to use the island as refuge in case hostilities began with the king, Louis XIV.  Instead, Fouquet was arrested and incarcerated.  

Vauban was not happy with the existing citadel, thinking the interior too cramped and the walls too low, so he modified the citadel more to his liking.  The walls were raised so that there were higher than the envelope, and cavaliers were added to the three land facing bastions, providing a fall back position in case the bastion walls were breached.  The envelope is an unusual feature not found in many forts.  Encompassing the citadel's entire land face, it allowed easy communication along the whole of the outwork.  The downside to this design is that an enemy lodgment on the envelope makes the entire envelope untenable.  In contrast, a series of closely spaced outworks could be connected with small bridges that could be demolished to prevent further enemy advances.

Traverses were added to the envelope, and the covered way was redesigned and rebuilt.  The land face was the citadel's strongest aspect.

The seaward facing portion of the citadel was strong by nature, and a fausse braie and a balcon were the only additions to this face.

The weak portion of the citadel was across the harbor from high ground beyond the town.  On this section, the envelope tapered off, and a tenaille fronted the walls.

In 1761, a British force bombarded the citadel from the high ground beyond town and breached the walls, forcing the citadel's surrender.

Arriving by ferry, tourists enter the gate through the envelope to the ditch below the Bastion du Dauphin.  On the right-center of the panorama you can see the envelope tapering off and in the distance the Bastion du Gouverneur.  At left-center you can see the Bastion Saint-Louis.  Next, we will walk toward it.

This is from the ditch between the Bastion du Dauphin at right and the Bastion Saint-Louis at left.  In the bastion face you can see openings for cannon to protect the ditch.  An infantry firing position is in the ditch at right.  Next, we continue left along the path.

This 360 degree view, complete with distortion, of the Porte du Donjon.  Bastion Saint-Louis is at right, and Bastion du Mer is at left.  Before we enter the gate, let's investigate the envelope.

This is the gate through the envelope.  Let's head back into the envelope to investigate it further.

Here we can see the counterguard in front of the envelope.  The covered way, not very clear here, is in front of the envelope.


Further along on the envelope, you can see the demi-lune to its front.  It featured a traverse to protect men on each side from enemy fire to their rear.  In front of the demi-lune is the covered way, with places of arms at the corners where troops could mass protected from flank fire by traverses.

Next, let's enter the Porte du Donjon and see the courtyard.

The original design was cramped, but after the 1761 siege the arrangement of buildings was improved to allow for greater troop mobility.

Le Grand Quartier

The citadel's most distinctive feature is a circular powder magazine inside the Bastion du Dauphin.  It dates to Fouquet's construction.


Casemates within the citadel can be visited.  Note the exhaust on the ceiling.

From Bastion du Dauphin there is a good view of the envelope and the traverses atop it that protected troops from enfilade ricochet fire from the town side of the citadel.

Looking the other direction from Bastion du Dauphin you can see the section of the citadel facing town.  This was the area that the 1761 British besiegers focused on.

Harbor View

Ferry View


The British siege was conclusive proof that the town of Palais also needed fortification - something that Vauban had clearly seen but had been unable to facilitate. 

 By the time the French government got around to fortifying the town in the late 1860s, the design was already obsolete in light of modern rifled artillery.

Like earlier fortifications, these included some depth.

Unlike forts of Vauban's time, 19th century fortification often featured a counterscarp that included firing ports facing the ditch.  Let's take a look inside...

Note there are firing ports between sections.

Two reduits, or redoubts, were placed on the covered way where demi-lunes might be found in earlier times.

In 1944, the Allies considered a plan to invade Belle Ile by amphibious and airborne forces.  This plan was associated with Operation Chastity, a canceled artificial harbor on the River Auray.  German guns on Belle Ile could have interfered with Allied ships coming to and from the port.

Copyright 2015 by John Hamill

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