The agreement between the Ministry of Culture and Microsoft was signed on July 21, 2025. A digital twin of the cathedral, drawn up in cooperation with the French start-up Iconem, will therefore be offered in the French State and integrated into the future Notre-Dame Museum in Paris. According to Brad Smith, president of Microsoft, this will be used to “Permanently preserve in digital form every detail of Notre-Dame, ensuring that its structure, its history and its symbolism are protected and accessible for future generations”.
Digitization is based on advanced imaging technologies, combining high -resolution photogrammetry, drone readings and artificial intelligence algorithms in order to restore architectural reality as close as possible.
Three main actors structure the project. Microsoft provides funding, calculation capacities and AI solutions. Iconem coordinates the capture and assembly of the 3D model. The Ministry of Culture is piloting the operation via the Heritage Institute, ensuring scientific supervision, data sovereignty and access to public collections. Microsoft will donate the model to the state once the project is completed.
During the 2019 fire, the absence of an exhaustive digital model had completed the catering. If partial surveys existed, carried out in particular by laser scanning in 2012, the extent of the claim revealed their insufficiency in the face of the challenges of precision and transmission. The recent reopening of the cathedral, after five and a half years of work, reinforced the interest of a digital twin to accelerate diagnostics, future interventions and scientific documentation.
Artificial intelligence occupies a transversal place: it allows the massive assembly of data, optimization of 3D rendering, detection of wear or defects and, above all, the temporal comparison of the monument states. “It will be an essential historical resource, usable in one, two or even three centuries”Brad Smith point.
The purposes of this digitization are multiple: predictive maintenance based on the analysis of microcoffresses, creation of XR (“Extended Reality” experiences) for the public, and facilitation of interdisciplinary research on materials or the evolution of buildings. The model created will be integrated into the museum dedicated to Notre-Dame, but also shared with scientific and heritage institutions for both training and documentation.
The operation will follow the model implemented for the Saint-Pierre Basilica of Rome, where more than 400,000 images treated with IA algorithms have enabled the development of a digital model of unprecedented precision. The two companies of the Notre-Dame project, Microsoft and Iconem, had already produced digital copies of Mont-Saint-Michel (2018) or the Olympia site in Greece (2022), systematizing the use of the digital twin as a museum, scientific and educational tool. The digitization in Notre-Dame aims to become a reference resource, both for France and for the international scientific community.
Additional collaborations are planned with the National Library of France for the digitization of opera sets, extending the logic of digital ecosystem around heritage.
