Inheriting spatiality and materiality of Gourara’s vernacular stone defensive architecture (Algerian Sahara)

The Gourara is a southwest Algerian Saharan region located on the ancient caravan trails linking sub-Saharan Africa to the Atlantic shores and the Mediterranean world. It is characterized by a set of fortified settlement oasis forming a network of more than four hundred defensive structures situated around the Timimoun sebkha, salty soils of this early lake human settlement on the Meguiden edge, an erosion glacis of the Continental Intercalaire sandstone cuesta area. By using a space anthropological approach prevailing oral tradition we have tried to understand the defensive inhabited spatial organization and identify the stone defensive structures typology. Through the morphogenesis of the inhabited space of five qsūr composed of fifty fortresses, occupied or abandoned, their toponymy is revealed contributing to the human settlement history restoration. This fortified vernacular inhabited space legacy is analysed through the spatiality and materiality of ruined defensive structures, between perceived and lived space, to identify the former builder’s stone constructive culture heritage. Far from the idealized images of Saharan oases, the Gourara’s vernacular stone architectural defensive archetypes identification reveals the absence of earthen constructive defensive structures despite clay wall coatings appearances. The fortresses and their landscape are identified as the establishment of ancient limestone and sandstone defensive constructive know-how with vertical wells dug one hundred meters into rocky peaks. The building technique is based on curved and right-angled stone masonry of the defensive walls as well as circular and squared angles towers and isolated watchtowers ruined defensive structures. The fortresses toponymy, water system and cemetery position together with saints’ tomb structures highlight the territory defensive system and stone architecture construction technics allowing to follow throughout time this Saharan stone building culture development from Roman Limes up to 19th century French colonisation.