Mapping of the Multi-risk Analysis for the Cultural Heritage of Sardinia from the Pre-Nuragic and Nuragic Periods: Initial Results of the RETURN Project

Sardinia's cultural heritage features unique prehistoric structures from the pre-Nuragic and Nuragic periods (5th–6th centuries BC). These include Nuraghi, giants’ tombs, sanctuaries, Domus de Janas, dolmens, menhirs, and megalithic circles. Given their complexity and the increasing threat from climate change, a comprehensive database and spatial mapping system are vital for their preservation. This study presents initial findings from Project RETURN (multi-Risk sciEnce for resilienT commUnities undeR a changiNg climate), which focuses on systematic risk analysis for Sardinia's cultural heritage. A unified database was created using public inventories, standardizing data and assigning simplified attributes based on monument dimensions (e.g., tall, subterranean). GIS tools enabled precise georeferencing, material characterization (via lithological maps), and automatic exclusion of sediment categories based on proximity and area size. Each structure was assigned vulnerability levels (Very Low to Very High) based on geometry and construction material, in relation to four hazard types: hydraulic, hydrogeological, seismic, and wildfire. Hazard data from regional sources were normalized and matched to monument locations. This allowed for the generation of both individual and multi-risk maps using a consistent five-level classification system. The resulting spatial analyses provide valuable insights into the exposure and resilience of heritage sites across Sardinia. These findings support informed decision-making for conservation efforts, with risk visualizations available at both site and regional scales.