  The paper concerns the definition of a novel ontology for cultural heritage
based on the concept of digital twin. The ontology, called Heritage Digital
Twin ontology, is a compatible extension of the well-known CIDOC CRM ISO
standard for cultural heritage documentation and incorporates all the different
documentation systems presently in use for cultural heritage documentation. In
the authors' view, it supports documentation interoperability at a higher level
than the ones currently in use and enables effective cooperation among
different users.
