A beacon of history and of military architecture, the Château de Joux is one of the Franche-Comté region’s most emblematic monuments. Just 5km from Pontarlier and only 15km from the Swiss border, the chateau sits high above the passage de la Cluse, overlooking this narrow pass through the Jura mountains. This strategic military and trade route links the areas of Champagne, Flanders and the Haute-Saône with Italy and Switzerland.  Joux is the only example of a military fortress in France to represent the evolution of military architecture over the past 1,000 years. Over these 10 centuries,  Joux  has been repeatedly enlarged, remodeled and reinforced to withstand the technical progress of warfare and artillery. From the feudal lords of Joux to the King of France via the Dukes of Burgundy and the Spanish monarchy, Joux has passed through the hands of many illustrious owners who have remodeled it according to their needs.

In the 18th and 19th centuries it also served as a prison to incarcerate anyone threatening public order or the safety of the State. Famous prisoners such as Mirabeau and Toussaint Louverture were held here.  The chateau today is made up of 5 rings of fortification, 2 hectares of buildings, 250 rooms, 3 moats and 3 drawbridges. Open to visitors since 1954, it was sold to the Pontarlier-La Cluse and Mijoux municipal syndicate, now called the Grand Pontarlier District Council. Registered as an historic monument since 1996, the chateau has managed to retain its historical importance in an unspoilt natural setting.

What is the origin of the name Joux?

The etymology of the word Joux comes from the Latin, Juria, meaning “mountain forest” and from the Celtic word Jor meaning “forested hillside”. Jura or Joux were originally used to describe a large area of forest. Indeed, the Jura boasts one of France’s most magnificent pine forests, the forest of Joux. In Switzerland, not far from the chateau,  the word Joux has given its name to a valley and a lake.

The mountains surrounding the Chateau de Joux have significant forested areas. The wood was used for heating, building and industry. The sap was used to make glue, fuel and insulation. These raw materials, essential for daily life, established the region’s wealth.

Architecture? One thousand years of it!

Overlooking la Cluse, the chateau de Joux protects and controls a highly strategic trade route and military highway. This position has been coveted since ancient times. From the Middle Ages, the Joux family established its seat of power on these lands and fortified the rocky outcrop with an initial chateau. In the 15thC, the powerful Duke of Burgungdy, Philip the Good, bought the chateau from descendants of the Joux family. Thereby extending his power over the areas bordering the earldom of Burgundy and safeguarding the Cluse pass and the route to his rich lands in Flanders.

In the 16thC, by means of inheritance, the Joux fortification passed into the hands of the Spanish crown who ruled over a vast area covering Spain, Flanders and kingdom of Naples. The chateau de Joux became a highly important logistical base for the safe movement of troops, weapons, supplies and merchandise. Its position on the border attracted the attention of the French king Louix XIV in the 17thC. This expansionist king extended the borders of his realm by taking over the region of Franche-Comté in 1678. The military engineer Vauban introduced modifications to the fortifications won over from the Spanish in order to create a continuous border around the country, creating the notion of an exclusive domain.

Defence of the eastern border was dependent on the bastions of Belfort, Besançon, the Salins forts and the chateau de Joux. At the end of the 19thC, after the French defeat in 1871 and the loss of Alsace-Lorraine, the Eastern border was reinforced. A new programme of reinforcement was planned to transform the strognholds according to a system developed by General Séré de Rivières. The chateau de Joux was renovated, in one last major campaign of work.

The fortress of the Joux Lords

The earliest mention of the chateau de Joux dates back to the medieval period. In 1034, it was probably not much more than a simple wooden garrison, built to control and defend the passage of La Cluse that it overlooks.

The lords of Joux cultivated their rich lands, managing the forests and natural resources, but also raising taxes and tolls on the inhabitants, traders and pilgrims. This income allowed them over time to reconstruct the stone castle. From the 12thC onwards, the chateau included a keep surrounded by round towers and two layers of ramparts. Very few archives or ruins have survived from this period.

The 15th and 16th centuries: a more or less flourishing renaissance

In 1454, the descendents of the Joux Lords sold the castle to the Duke of Burgundy. This powerful character is a rival to the French king. He owned a vast domain including Burgundy, Flanders, the Netherlands and Picardy. The Chateau de Joux was a strategic acquisition since it formed a connection between these different regions. For the duke, it was an opportunity to establish his domination over the wool and salt route. He was not resident in the chateau but installed a garrison, governed by the count of Neuchâtel. In 1486, the latter decided to modernise the castle which now included three layers of ramparts. A large tower, the horseshoe tower, to protect the entrance against the fire power of an increasingly effective artillery that included bronze canons.

From the 16thC to the 17thC, this highly prized castle passed into the realms of the French kings in an alliance with Sweden, then the Spanish monarchy, which had inherited the wealth of Burgundy. The castle was in a poor state of repair. It was, for the most part, rebuilt in the second half of the 17thC. Lodgings for soldiers and the governor were built in the third layer of fortification and the first layer. A fourth layer of protective walls was added, known as the outer fort.

In 1678, Louis XIV once and for all extends the borders of the French kingdom to Franche-Comté. The chateau de Joux is transformed by the military architect Vauban to stop an enemy army, arriving from Switzerland. It becomes part of a border defence system that also includes the bastions of Belfort, Besançon and the Salins forts.

Vauban plans around the rocky outcrop and the existing buildings. He adapts the fortifications to the contours to create five layers of staggered, fortified defences, combining the requirements of the infantry and the artillery. The first and second layers are strengthened. On the third layer, the medieval artillery tower, known as the Horseshoe tower, is remodeled on 3 floors and a fortified tower is added at the opposite end of the curtain wall. The 4th layer is divided in two by an angled  curtain wall flanked by two fortified towers. The 5th layer of protection is completely remodeled.

Other than the fortification works, Vauban equips the castle with the amenities necessary for life in a garrison of 5 to 6,000 men: barracks for troops and officers, comfortable lodgings for the governor, a chapel, storage for food and ammunition and a large well for the water supply. A gate of honour in the curtain wall of the 4th layer acts as a reminder that the chateau is part of the glory of Louis XIV.

The 18thC: rules and control

In the 18thC, work continues according to the plans initiated by Vauban. The 5th layer of protection is completed. A large chapel is built within it. The rules governing the life, arms and uniforms of the soldiers is reflected in the architecture. The function of each building is clearly defined. The grade of each soldier is replicated in the space he is allocated. The officers are housed in the highest fortifications of the castle (layers 1 and 2) whereas the troops are quarted in the 5th layer.

This is also the period in which the castle is turned into a State prison. The buildings of the 1st layer of protection and the towers become cells for prisoners locked up according to signed and sealed instruction from the king. The soldiers in the garrison fulfilled the role of prison wardens.

Changes of the 19thC: Séré de Rivières' semi-buried fort

In 1813, the European monarchies formed an alliance against the Emperor Napoleon 1st. Whereas the Emperor had previously been fighting battles far beyond the Empire’s borders, now it was France that was under threat. The Austrians beseiged the chateau de Joux. With considerable effort they managed to install their artillery on mount Larmont. The chateau was now within reach of their firepower. It is badly damaged. The following year, it was the Swiss who took the chateau to force Napoleon 1st to abdicate for a second time. In the second half othe 19thC, the chateau was restored and in 1844, the lower Larmont fort, known as Mahler, was built opposite the chateau. The French defeat of 1871 and the loss of Alsace-Lorraine encouraged the French Republic to launch a new programme to strengthen its eastern border. The chateau de Joux became part of this new line of defence. The 5th layer of fortifications is remodeled and englarged to become a modern semi-buried fort in the Séré de Rivières style. All the buildings were covered in several metres of soil to lessen the blow from incoming shells and to hide the fort from enemy sight. From 1880, the work came under the supervision of the Engineers commander, Joffre (later to become Marshall Joffre).

In the 20th Century

Despite the two World Wars, the Joux fort did not benefit from any further architectural improvements. Following hte armistice in June 1940, the Germans occupied the fort and removed all the metal in order to make weapons. The chateau de  Joux lost its strategic military interest. In 1954, it was opened to the public. Then in 1968, it was sold to the Pontarlier-La Cluse and Mijoux municipal syndicate, which became the Grand Pontarlier District Council (CCGP). Since then, renovation work has been undertaken by the CCDP to preserve this historic monument, a gem of military architecture and showcase of national and international history.

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