This lecture presents the Lausanne Time Machine project, focusing on the digital urban history of Lausanne in 1832. It covers the intersection of cadastral and population data, the creation of a search engine, and the spatial organization of professions. The work includes manual data cleaning, dataset merging, website creation, and the production of final maps using heatmaps. The lecture concludes with insights on imperfect data merging, the use of Google Maps for additional information, and the classification of professions in Lausanne in 1832.