The Grand Exhibition of Line 18 at the Lumen

Line 18 will be the first new metro line built in the Île-de-France region in 30 years. Designed by the Société des grands projets (SGP), it will ultimately connect Orly Airport to Versailles-Chantiers, serving the Saclay plateau, the region's leading scientific and academic hub. A first section, between Massy-Palaiseau and Christ de Saclay, will open to the public in late 2026, transforming daily travel for 70,000 students, researchers, and workers on the plateau.

Designed and presented by the SGP, this exhibition offers a behind-the-scenes look at an extraordinary construction project through objects and materials taken directly from the field: soil cores collected during geotechnical surveys, identity soil samples, and bricks and paving stones made from excavation spoil — a tangible example of how construction materials are being reused.

Visitors will also be able to see the technical components that keep Line 18 running: a sample of the third rail with its support and fastening clip, as well as rail samples and their fastening systems, both in tunnel sections and on the viaduct. The centerpiece of the exhibition is the cutting wheel from the Awa tunnel boring machine, a 250 kg object that testifies to the power of the machines that dug the line's tunnels.

The exhibition also showcases prototypes designed for future stations and trains: metro seating and a waste bin designed for passenger spaces, along with a large-scale illustration of the Massy-Palaiseau station platform. Additional objects are under consideration, including a sketch of the artwork "Tandem," created for the Université Paris-Saclay station, and a scale model of the Line 18 train's front end.

Alongside this trail of objects, posters and videos retrace the major milestones of the construction project: tunnel boring, the building of the viaduct, and the fitting-out of the elevated stations at Polytechnique, Université Paris-Saclay, and Christ de Saclay.

The exhibition will also feature a talk with one of the project's architects and an artist who took part in the line's cultural programme, discussing station design and the artistic dimension of the Grand Paris Express.