Mapping Mosques of Old Algiers Before the French Colonial Demolitions: Through Albert Devoulx Manuscript (1870)

This article presents the precolonial map of religious buildings in old Algiers (Casbah) that is based on an unedited manuscript that goes back to 1870. It helps to reconstitute the original urban fabric, locate the disappeared buildings, and identify the impacts of the demotion actions on the town. Among the 167 buildings that existed at the arrival of the French army, only forty-seven buildings remained at the time of the author. The approach combines the literature sources with old maps and the detailed sketches that were undertaken by the Genie Militaire. The overlapping of the historical data on the present satellite images was made through georeferencing and the use of geographic information system, ARC-GIS 10.6. Beyond the understanding of the present urban geometric complexity of Casbah, this work helps in colonial historiography and raises historical consciousness in architecture and planning.