In August 2004, French police officers conducting a routine training exercise in the subterranean limestone quarries beneath Paris’s Palais de Chaillot stumbled upon something entirely unprecedented: a fully functioning 400-square-meter cinema complex hidden over 50 meters below the surface.
The space was equipped with a full-sized projection screen, professional 35mm projection equipment, a well-curated library of classic 1950s film noir cinema, a bar stocked with aged whiskey, and a dining lounge with tables and chairs wired with electricity siphoned from the city power grid above.
Dossier Highlights
- Location: Beneath Trocadéro / Palais de Chaillot, 16th Arrondissement.
- Architects: "La Untergünft" (Untergunther), a branch of Les UX.
- Discovery Date: August 23, 2004 by French National Police.
- Current Status: Sealed by municipal authorities; equipment evacuated.
Who are Les UX?
Short for L'Urban eXperiment, Les UX is an underground collective formed in the late 1970s. Unlike casual trespassers or graffitists, Les UX functions as an elite clandestine society of urban artisans, architects, cartographers, and engineers dedicated to restoring non-public historic spaces throughout Paris.
"We aren't vandalizing or trespassing for fame. We restore what the city forgets, enjoying cultural preservation in total silence." — Anonymous Les UX Spokesperson
The Pantheon Clock Operation
Perhaps their most extraordinary feat occurred inside the Panthéon in Paris. Over a year-long period between 2005 and 2006, the Untergunther faction established a secret workshop in a hidden cavity inside the Panthéon dome. Night after night, master clockmaker Jean-Baptiste Viot repaired the monumental 1850 Wagner clock that had been left frozen and neglected by the state for over forty years.
When the restoration was completed, Les UX revealed their secret presence to the Panthéon administrator, presenting a fully ticking clock mechanism. Rather than celebrating their craftsmanship, the French government attempted to sue the group, though charges were ultimately dismissed in court due to lack of criminal damage.
Navigating the Subterranean Network
The Paris underground stretches across over 300 kilometers of subterranean stone quarries, bone ossuaries, sewer galleries, and abandoned metro stations (known as stations fantômes). While official public access is strictly restricted to the official Catacombs Museum at Denfert-Rochereau, hundreds of subterranean enthusiasts known as cataphiles maintain intricate map archives to navigate the lower levels beneath Paris.
For more official verification on Paris historical monuments and subterranean preservation laws, consult Paris Official Catacombs Historical Registry.