Deep in the heart of Paris, a series of underground tunnels snakes across the city. They cross into unkept public spaces from centuries ago that have since vanished from collective memory – abandoned basements, catacombs, and subways hundreds of miles apart.

Only a few groups still traverse these subterranean streets. One that came into public view a few years ago, Les UX (Urban eXperiment), has since claimed several refurbished developments, including restoring the long neglected Pantheon clock and building an underground cinema, complete with a bar and restaurant.

While the streets of Paris are tame during the day, at night is when Les UX really comes alive. A typical night might involve hiding in the shadows away from potential authorities roaming the streets, descending into the tunnels through a grate in the road, and carrying materials to an agreed upon drop off location. Other nights might involve wedging and climbing over pipes and ladders, following the routes into the basements of buildings left unguarded.



Members have claimed to be able to access every last government building and telecom tunnel in the city. Even members of the Parisian police force can’t help but admire the knowledge and skills of the underground hackers. One of the members, [Lazar Kunstmann], was able to describe the process of stealing a Picasso – apparently an easy enough task for anyone who has the time to observe the lax security within the Museum of Modern Art of the City of Paris.

Granted, sneaking around the tunnels and under secured buildings isn’t as easy as some members may make it sound. Accessing the tunnels – an illegal but rarely enforced act – is already quite difficult. Finding an unlocked entrance can be an exceptionally long trek from the nearest subway, and knowing the secret entrances can require connections with other urban explorers. Even crawling around in the tunnels is a filthy and exhausting activity for the uninitiated.

Shadowy Beginnings, Professional Present

The organization had its start some time in 1981, beginning with the stolen plans for many of Paris’s underground tunnels and passageways. They have since grown into an enclave of anonymous artists and concerned citizens who have come together to restore medieval crypts and celebrate the forgotten sites of Parisian past. Few have ever come forward about their existence apart from [Kunstmann], who has since spoken to magazines and published a book based on his experiences.

According to his account, the organization is divided into several subunits – one that specializes in infiltration (an all-female team known as the Mouse House), one that couriers internal messages and communicates over a coded radio network, one that keeps a database of organization activities, one that organizes the staged shows and readings, one that specializes in photography, and one that works on restorations (known as Untergunther).

The latter team is made up of more experienced professionals – architects and historians, often with a personal interest in the object of restoration, as in the case of the Pantheon clock. Professional clockmakers such as [Jean-Baptiste Viot] assisted in the multiyear project, painstakingly recreating gears that were too rusted or worn to be restored and refurbishing other parts of the clock that had been corroded or weathered from years of neglect. When the newly restored clock was revealed in October 2007, however, they were met with attention from the Paris police force.

While the group may have begun as a clan of rebellious teenagers, it eventually grew into something far more sophisticated. The entire operation for the Pantheon required special care taken to understand the mechanisms behind the clock tower and the techniques used by its original architects. [Viot] especially wanted to undergo the project since oxidation had so ruined the original works that they would soon be impossible to repair without replacing every part. As a professional horologist, he had the skills required for the job, and Les UX had been looking to undergo the restoration for years. The team built a workshop outfitted with armchairs, a table, bookshelves, a minibar, and red velvet drapes concealed into wooden crates to blend into the paraphernalia stored within the monument. Only at the dead of night was the clock repair equipment brought out. The group did everything from updating the workshop’s electrical wiring to growing their own vegetable garden on the terrace. Even if members were caught at night, a fake badge was enough to get past the security guards.

The autopsy of the clock revealed that someone appeared to have sabotaged the clock, possibly a Pantheon employee tired of winding the monument once a week. They cleaned the parts in a hot bath of soap, ammonia, and oxalic acid, scrubbing and polishing every surface. Then they replaced or recreated pulleys, cables, the broken escape wheel, and missing parts like the pendulum bob. By the time the project had finished, the team felt that it would be a good idea to notify the authorities about their work in order to ensure proper future maintenance of the public monument. They offered to meet the director of the monument in person, but were startled to find that the authorities refused to believe their story, instead suing UX at 48,300 euros and up to a year of jail time. The then-deputy of the monument even hired a clockmaker to re-sabotage the work. (The clockmaker refused other than disengaging the escape wheel, the same part that had been sabotaged the first time.)

Authorities Barge In

The Pantheon wasn’t the first time the police were brought face-to-face with a Les UX project. Back in 2004, a widely covered story emerged of a police force discovering an underground movie theater run by the group, containing a movie screen, bar, and kitchen. The space was equipped with telephones and electricity, with movies ranging from 1950s classics to modern thrillers. The police were less than happy with their discovery, but when they returned for a formal investigation, the space had been entirely vacated.

In fact, the authorities so opposed the group’s activities that they began a new unit to track the group through the city’s sewers and catacombs in an effort to identify members of the group and charge them for their actions. The Centre of National Monuments similarly replaced their administrator after their embarrassment over not noticing how the group had entered the Pantheon building so easily. Over the course of the scheme, large planks were even carried up the clock tower in order to construct a small workshop inside the space.

As for the trial against the restorers, the judge ruled in favor of the Untergunther members. It may have been seen as a relief, but it was definitely not the expected culmination of the project – the main reason the project was revealed in the first place was to provide authorities with the information they needed to wind up the clock so that it would work again.

Some members of Les UX certainly felt that they had to do something to help save the lost public works of Paris, especially if the local government wasn’t going to take action. Others were simply excited to continue celebrating the Parisian underground world. Many had been students in the Latin Quarter in the 80s and 90s, when secret parties were common to find in the tunnels.

While the Pantheon remains the group’s proudest feat, there are still active events going on and restorations in the works. Past exploits have included rock concerts for up to 4000 people in the quarries, projections off a locked film theater (showing subtly subversive programming by international filmmakers), and an art exhibition in a supposedly seal-off underground gallery. Members were even known to travel through a series of interconnected caves beneath the Palais de Chaillot, across the Seine from the Eiffel tower, every Bastille day to watch the fireworks from the roof of the building.

While it’s not affiliated with Les UX, there are a number of videos online that show some parts of the Paris underground scene and the artists affiliated with the tunnels.