This project aims to reconstitute, understand and publicly debate the history of the HIV epidemic in Paris, by experimenting an original research strategy. The project is based on the collaboration between a team of historians of medicine (Sciences Po médialab), a team of architects and historians of architecture (Department of Architecture and Urban Planning, Université de Ghent) and a team of virologists (INSERM-Hôpital Bichat). Firstly, the project proposes an archeological approach, that is based on research from the traces of the epidemic in a specific site - the former Claude Bernard Hospital (porte de la Villette) which was destroyed in the 1990s. The Claude Bernard Hospital has been one of the most important place for clinical research and care in the early years of the HIVAids epidemic - it was within its walls that the samples leading to the isolation of HIV-1 and HIV-2 were obtained. Build in the early 20th century, it was entirely designed as a tool of control of infectious diseases and epidemics. This history was erased from the urban landscape following its demolition. The aim is to combine an inquiry into the history of the epidemic, the material history of care and the architectural and urban history of the hospital, to renew our knowledge of the history of HIV in Paris and in France. The archeological approach is not limited (contrary to classic historical methods) to "exploiting" archives and witnesses known a priori, and whose defintion depends on commemorative and institutional logics. As it works from an inventory of material traces linked to a site, this approach is able to excavate a part of the past that is "unknown", for example because it is associated to minority groups or to silenced or underrepresented experiences of the epidemics (such as non-medical healthcare workers). Secondly, the project proposes to extend this perspective towards a "molecular archeology" of the epidemic, thanks to molecular phylogeny analysis based on HIV sequences from the 1980-1990s. Benefiting from the major progress of phylogenetical tools, the aim will be to show how viral sequences can reveal new aspects of the history of the epidemic and can lead to new visual representations "revealing" the social. The project experiments an iterative approach of the biology/social sciences collaboration: the historical, architectural and ethnographic research feeding phylogenetical analyses and reciprocally. Beyond its scientific outcomes, the project will lead to the conception of a public exhibition on the archeology of Aids in Paris, highlighting the experience of minority populations (incl. African populations) and original visualisations of the epidemic, both urban and biological, which could renew the public debate on the history and memory of Aids.