In the heart of Paris, Île de la Cité once featured one of the most majestic palaces of medieval times: The Palais des Rois. Built in the early Middle Ages, only two parts of this grandiose palace remain: The Sainte-Chapelle, the largest and most daring palatial chapel of the time; and the Conciergerie, a medieval room of impressive dimensions, known for having served as a prison and housing the jails of Marie-Antoinette. These two unique buildings are a testament to an exceptional mastery of construction techniques that included ribbed vaults, an innovative consolidation system, iron frames, and load-bearing pillars with an impressive diameter.

Thanks to these attributes, these two buildings have stood for centuries and still attest to the magnificence of the palace of kings. But how did the builders of the time manage to work on wet and unstable soil? How did they maintain the 618 square meters of stained glass windows of the Sainte-Chapelle? How did they ensure the stability of the Conciergerie's Hall of the Soldiers, which could accommodate up to 2,000 people?

Thanks to quasi-imperceptible details accompanied by 3D explanations, archaeologists, architects, and historians reveal the ingenuity of the construction techniques used. We invite you to travel back in time and discover how the Sainte-Chapelle and the Conciergerie became the most accomplished buildings of the Middle Ages.