This paper investigates the ontology of 3-D replicas and simulations of archaeological and heritage sites. In the past 20 years, the use of new technologies for the 3-D documentation and reconstruction of cultural heritage has altered approaches to the analysis and interpretation of tangible heritage. The preservation and recreation of the past is becoming increasingly “digital.” Scholars are debating the authenticity of 3-D digital reproductions in heritage and archaeology. How should we consider these digital and virtual reproductions? Are they original digital representations of our cultural heritage or just virtual “fakes”? It is argued that it is not possible to define universal predetermined categories for the definition of “authentic” in the digital domain, since 3-D digital reproductions of tangible heritage are always influenced by the subjective interpretation of the creator of 3-D content. To support this argument, three case studies are presented that deal with the contested and controversial concept of authenticity in different domains: physical, digital, and a combination of physical and digital.