Integrated Digital Environments for the Knowledge and Management of Low-Accessible Cultural Heritage: A Multiscale Web-Based Framework

Low-accessible Cultural Heritage, including hypogeal sites, rupestrian architectures, and fragile structures, represents a major challenge for conservation, documentation, and continuous monitoring. These limitations stem from multiple inaccessibility factors, classified as physical (morphological complexity), asset risk (microclimatic instability), health and safety (structural vulnerability), managerial (lack of public access), and cognitive (lack of documentation). This research aims to transform digital models from mere representational tools into integrated cognitive and operational systems supporting decision-making and preventive conservation. The proposed methodological workflow is structured into five main phases: Preliminary Knowledge and Multidisciplinary Data Structuring (Ph1. PK–MDS), Comprehensive Digital Survey (Ph2. CDS), Development of Integrated Digital Models (Ph3. IDMs), Advanced Diagnosis and Monitoring (Ph4. ADM) and the implementation of an Integrated Digital Environment for Hypogeal Heritage Management (Ph5. IDE). Ph4 operates on two complementary scales: at the site scale, range-based point clouds enable the semi-automatic identification of extensive decay patterns, such as biological colonization. At the detail scale, the Random Forest algorithm enables the segmentation and quantification of material loss on frescoed surfaces through a diachronic comparison of historical and current data. Validated on the San Pellegrino complex in Matera, selected as a paradigmatic case study of low-accessibility hypogeal sites, representative of a broader system comprising approximately 150 rupestrian cult architectures, the methodology demonstrates how immersive digital environments function as shared knowledge spaces, supporting more informed, inclusive, and resilient heritage conservative management.