Mobile 3D recording as a means of digital preservation. An experience in documenting stone structures from the west bank of Aswan (Egypt)

This study presents our experience documenting stone structures during the 2022 Aswan-Kom Ombo Archaeological Project (AKAP) field season. Using a combination of smartphones and GIS software, we established a recording workflow for a week-long pedestrian survey at two prominent sites on the west bank, north of Aswan. These locations contain numerous stone structures that vary in position, typology, and function. WK71 is a cluster of Late Roman tumuli located on the plateau behind the modern village of Nag el-Qarmila, covering approximately six hectares. NH11 is similarly situated atop a plateau extending toward the river, just north of the village and namesake of the renowned rock art site of Nag el-Hamdulab (NH1). This site spans roughly 19.5 hectares and contains several archaeological features, including numerous stone structures of uncertain function and date. Satellite imagery was instrumental in the preliminary documentation and fieldwork planning. During the survey, we recorded the stone structures in 3D using smartphones, placing metric references on the ground to ensure accurate scaling and orientation of the digital models. To assess the accuracy and reliability of this experimental approach, we supplemented the documentation with additional 3D and linear measurements using other devices and recording techniques, such as digital cameras and Structure from Motion. Thanks to the inbuilt GPS/GNSS receiver, all stone structures processed through the smartphone app were embedded with global WGS coordinates, facilitating precise geo-positioning within the project’s coordinate system. Additional software allowed us to generate planar ortho-projections of each structure, which were then imported into the GIS project for vectorization and spatial analysis. This workflow enabled us to document over 140 archaeological features in a short time without compromising resolution or accuracy. Moreover, it allowed for a preliminary archaeological classification of these features before the field season concluded