As part of Paris' planned transformation for the 2024 Olympics, our concept for the Gare du Nord renovation and expansion is a "crystal cloud" floating over the original train station. This new departure hall is an embracing cloud-like space formed of intersecting spheres bringing natural light into the station and adding new areas for commercial, service, catering and business centers for co-working. It frees up space below for all arrival traffic to low directly out on the main level from the platforms of the original station. The cloud-like intersecting spheres, made of P.C. Ductile concrete with slices of matte sandblasted glass, produce an inspiring and iconic space in complimentary contrast to the original 1846 space by architect Jacques Ignace Hittorf. For the 2024 Olympics a temporary tower of light is formed of the five intersecting Olympic rings as intersecting spheres: an Okulux façade like stained glass is in the colors of humanity: A glowing invitation at night. Our conceptual strategy of the crystal cloud (90% constructed in prefabricated pieces offsite), allows no closures of the existing Gare du Nord, the busiest railway station in Europe.