“La Caverne du Pont-Neuf” is open !

This is one of the project’s greatest achievements and an absolute prerequisite for working on themagnificent oldest bridge in Paris: “La Caverne du Pont-Neuf” was designed to never compromise the integrity of this historic monument. Not a single screw or nail has been driven into the stone; the fabric is simply laid over the parapet.

During the installation, JR’s teams worked with historic preservation specialists to protect the bridge piers using straps and temporary fastening systems. The huge canvases were then lowered from the parapet and secured without ever touching the structure of the Pont-Neuf (Paris Center).

The project was particularly challenging due to river traffic and weather conditions. It required special permits so that Contraste Pro Artistique, a specialist in technical operations on the water, and the technicians from the Tollis, experts in historical restoration, could install the giant canvas at night from the Seine using four Zodiacs, cherry pickers, and a pontoon boat.

“La Caverne du Pont-Neuf” was designed in JR’s Parisian studios and then manufactured entirely in Brittany, at theAir Toiles Concept, a craft-based company based in Plougoumelen (Morbihan) and specializing in textile and inflatable structures.

For several months now, this company—which holds the “Living Heritage Company” certification —has been working on the technical design, the printing of the canvases, and the assembly of the entire structure. JR wanted to prioritize short supply chains and a controlled environmental impact.

The project even prompted the company to invest in new large-format printers and open a second workshop. “There will be a before and an after, ” explains its director, François Graceffa.

Engineers, design firms, 3D designers, fashion designers, printers, welders, carpenters, lighting technicians, fire safety specialists, boat pilots, aerial lift operators, and maintenance crews, etc. : The construction of “La Caverne du Pont-Neuf” brought together a wide range of trades, involving more than 800 professionals.

After more than a year of preparatory work leading up to the installation’s unveiling, a veritable hive of activity has been underway on the bridge since May 11— 300 people just for the setup—and will continue to work throughout the public opening and until the dismantling, which will conclude on July 13.

Did you know, for example, that Air Toiles Concept has set up sewing machines —and seamstresses— right on the construction site so they can make adjustments immediately if needed?

JR’s goal was not simply to cover the Pont-Neuf, as Christo and Jeanne-Claude had done before him, but to make a real rock appear in the heart of Paris. To create this trompe-l’œil effect, he visited numerous limestone quarries in the Île-de-France region as well as caves in Greece, which he photographed. Hundreds of mixed images were assembled into a patchwork to design a unique imaginary rock in the form of a 3D model.

All that remained was to install the structure and inflate it so that it would take its final shape. To get an initial idea of the result, a full-scale section was tested in a hangar at Orly (Val-de-Marne) earlier this year. Resistance to the elements—and even to a flood of the Seine—was studied.

It was on the night of May 20–21 that an 18-meter-tall “mountain” appeared right in the heart of the capital! Before the addition of the interior sensory elements: immersive sounds designed with Thomas Bangalter (formerly of Daft Punk), an olfactory experience, and augmented reality.