Notre-Dame is a massive cathedral, but when we look into its structure, it is supported by light components like flying buttresses and rib vaults. The cathedral is where weight was gain from lightness, and our design is very much inspired by that. We used the plan of Notre-Dame, a Latin cross, as our basic unit. Each one of this cross is only a half meter wide. Only one of these crosses may be too light to be count in architecture, but we used thousands of crosses to form vault and then build up the roof and create space inside. The Latin crosses are horizontally connected by glass crosses. When be look in distance, the crosses seem like floating in the air.Along the corridor, it is quite dim. But in the center, the light shines into space through large windows. The crosses cast mysterious shadows on the floor.The mirror on two sides of the corridor brings the crosses above down to the ground. The reflection is weightless, but it creates another spiritual world that makes the space more mysterious.Our design reflects the idea in Gothic architecture that the soul can get rid of the shackles of secular matters and get to heaven with the guiding light of God.We realized that Notre-Dame was a collective effort and wisdom of people over hundreds of years. The construction started since 1163 and then the cathedral was extended, damaged and restored for several times. With the respect of our ancestors' design, we decide to rebuild the roof and the spire as same as the original design and blend our modern reconstruction inside. The only change outside is some small windows are added on the roof. Visitors can enter the roof thought the towers on the west fa√ßade. The new space will be independent of the cathedral below in order to have little influence on the daily activities there.Our design can also reflect that people from France and over the world unite together trying to rebuild the cathedral. An individual may not help, but when people unite themselves together, they will be much stronger. Like the crosses hold up the roof, united people will bring back Notre-Dame again.