A wall of light in an underground lair. The artistic boldness of this idea is obvious to passers-by at La Défense's Grande Arche RER station. They discover an array of colors and light covering an 18-meter-long, 4-meter-high stained-glass window. From bluish white to cobalt, ultramarine and turquoise blues, the shapes diffuse their colored waves in an astonishing symphony.

The work is located at the end of the platform, at the head of the train when the destination is Paris. The other ends of the platforms are also occupied by two other works of art: Bas-relief en cuivre and Boréale.
 

For this delicate work, Hervé Mathieu-Bachelot, a veteran of underground creations, combined his talent with that of André Ropion, a Parisian craftsman who has lived in the Loir et Cher region since 1990 and is an expert in the restoration and creation of stained glass and mosaics. He notably created a set of stained glass windows for the Basilique de Paray-le-Monial in 1984.