This two-and-a-half-day in-person training and networking programme is dedicated to Reactive Heritage Digital Twins (RHDT) and their application to cultural heritage conservation, restoration and valorisation. RHDT is an advanced approach that moves beyond static 3D documentation by integrating semantic interoperability, real-time data (IoT/IoCT), simulation services and collaborative AR/VR environments to support monitoring, decision-making and collaborative interpretation across different scales of cultural heritage, including cultural artefacts, historic buildings, archaeological sites and landscapes.