Mapping Ancient Battlefields in a multi-scalar approach combining Drone Imagery and Geophysical Surveys: The Roman siege of the oppidum of Cabezo de Alcalá (Azaila, Spain)

Abstract

Abstract The archaeology of battlefields has developed its own fieldwork techniques, based on pedestrian survey, aerial photograph analysis, metal detection surveying and, more recently, LiDAR data. Until now, this combination of tools had not included low altitude imagery obtained with drones. Thus, multispectral and thermal data acquired at low altitude with a drone are applied here for the first time, combined with the more usual tools, to identify the remains of an ancient battlefield. The objective of this project has been to map previously unknown remains of the siege of the town of Cabezo de Alcala de Azaila (Spain) in Roman times. A multi-scalar approach has applied non-destructive technologies: historical aerial photographs, close-range aerial photography by drone with multispectral sensors, LiDAR data, GIS and metal detection surveying. The combination of these techniques has revealed a complex system of military structures around the oppidum of Cabezo de Alcala de Azaila, the first time such structures have been found in the Iberian Peninsula and which attest the military destruction of the town. In short, mapping the siege with a drone has enabled a new advance in the research, conservation and dissemination of ancient battlefield cultural heritage.