Unveiling AlUla Old Town: A Transdisciplinary Approach to the Study of the Built Heritage in the Northwest of Saudi Arabia. Integration of Building Archaeology and Mortar Analysis

AlUla Old Town is an uninhabited site located in the AlUla valley, Northwest of Saudi Arabia. The preliminary results from the analysis of the standing architecture and of the archaeological record from archaeological soundings shows that the site had various occupational phases. Such occupational phases, and the nature of the resources available (e.g., sand-rich soil, and palm trees), led to the creation of a unique vernacular architecture that, over the time, accumulated signs of transformation. Such stratification, and the limited number of chronological sources available led the archaeologists to design and implement a transdisciplinary approach for the analysis and dating of the structures. Among the various activities included in such approach, the analysis of the historic mortars was considered having a high informative potential in relation to the historical development of the buildings. Archaeologists worked with specialists in mortar analysis to collect earth mortar samples and identify similarities and differences in the building materials and technologies used across the settlement, as well as to isolate organic or inorganic dating material. This paper describes the approach used in the MuDUD project to investigate the built heritage of AlUla Old Town, with a particular emphasis on the use of the mortar analyses.