Inhabited ruin heritage: stone and water in the defensive system of Tala Aougrout. (Gourara, Algerian Sahara)

Abstract

Tala Aougrout is one of the fortified settlement oases forming the network of defensive structures of the Gourara. It is located in the south west of Algeria, on the ancient caravan routes linking sub-Saharan Africa to the Mediterranean world. Thanks to its geographical position, at the foot of the Tademaït plateau, Tala Aougrout has benefited from abundant waters, which have allowed the establishment of five ancient fortified human settlements. Today, the vernacular architecture defensive system is caught in the midst of the city development characterized by phases of demolition and abandonment of the urban fabric. Despite an advanced state of ruin, these ancient defensive human settlements are still inhabited and provide access to knowledge of the site transmitted by the "living word" (oral tradition). Through this "lesson of the inhabited ruin", we analyze the constructive logic of this defensive structure in its mastery of stone and water, specific to this Saharan region. Hence, the study of the materiality of the transformation of the site, in close mimicry with nature and stone constructive know-how, identifies two key elements of the defensive system: Lehfi (ditch) and Foggara (collecting and transporting water device).