Investigating lost medieval villages using Satellite and Airborne Laser Scanning : the case of Yrsum in Basilicata (Southern Italy)

The phenomenon of lost villages in the late Middle Ages is a topic as complex as it is stimulating for historians and archaeologists. It raises many questions regarding the causes of the abandonment. To answer these questions, systematic studies are required along with detailed surveys of the investigated areas in order to detect the lost villages and to understand the relationships between sites and landscapes. In this context many problems arise, among them, for example, the detection and identification of anthropogenic and geomorphological features. This is a difficult task, especially for complex areas and settlements built on the top of hills and mountains, as in the case of Yrsum, located in the Basilicata Region (Southern Italy). In Yrsum, field work, the study of historical sources, the processing and interpretation of satellite imagery and DTM derived from Lidar survey, allowed us to reconstruct the urban shape of the village in its different functional and spatial components as well as to identify features linked to geomorphological pattern. This opens new investigation perspectives for both the assessment of endangerment of the cultural site and the study of the factors which caused the abandonment of this emblematic study case