Skip Navigation

UNESCO World Heritage Sites

UNESCO World Heritage Sites

Royal Saltworks at Arc-et-Senans

For a region that enjoys a high level of anonymity among the outside world, it almost seems incongruous for Franche-Comté to offer such a wealth of attractions. From mighty historical buildings to heavily fortified towns, UNESCO has afforded a great number of locations throughout the area with the illustrious World Heritage Site status. Nowhere is the prestige of such a title more deserved than the Saline Royale – the Royal Saltworks at Arc-et-Senans.

Salt throughout the 18th century was a highly valued commodity, so much so that the French government even imposed a tax on salt consumption. With such an industry thriving throughout the Franche-Comté regions of Salins-les-Bains and Montmorot, it was only a matter of time before a grand factory would be constructed to optimise the performance of sourcing and production.

Claude-Nicolas Ledoux

Located near the Forest of Chaux and standing among gloriously unspoilt scenery, the magnificent Royal Saltworks is a construct delivered from the mind of 18th-century architect, Claude-Nicolas Ledoux. Ledoux, a Parisien, was a keen exponent of an early Enlightenment project that promoted architectural design based around rational geometry. As such, the structure has a form that embraces unbridled ambition and is unlike anything that came before it, with the rigid geometry of the designs complemented by Ledoux’s grandiose vision of a modern factory environment.


Though Ledoux would develop plans for a wholly circular design featuring an ‘ideal city’ built around the factory, the Royal Saltworks would ultimately take on a semicircular design. Construction began in 1775 under the patronage of Louis XV, but the onset of Revolution, and the resentment focused towards the state monopoly of the region’s salt mines, ensured that the ideal city envisaged by Ledoux would remain a dream.


The Royal Saltworks is a reminder of the riches delivered to the region by such a modest and traditional industry. Yet, the legacy of the structure provides so much more. Declared a UNESCO World Heritage Site in 1982, the Royal Saltworks at Arc-et-Senans would take on a new life following the cessation of production at the factory. Housing refugees of the Spanish Republic, and being occupied by the Nazis for two years during the Second World War, the building has undoubtedly experienced far more than its fair share of excitement, so for Ledoux’s opulent masterpiece to enjoy the acclaim and protection afforded by its UNESCO listing is a reward well deserved.