This paper focuses on documentation and conceptual modeling of historical information of an immersive Virtual Reality experience scenario and its archival sources, in this case, Block 15. Block 15 is developing by the Department of Informatics of Athens University of Economics and Business. It is the first immersive Virtual Reality production and one of the first across Europe focusing on a site of difficult heritage in Greece. This site is Block 15 of the Haidari Concentration Camp in Western Athens that during Greece’s wartime was not only the largest but also the most notorious German Concentration Camp. The scenario of Block’s 15 production is based on both primary and multimedia archival sources. The documentation process is being applied to the scenario’s historical information. After this process, a conceptual model for the scenario’s historical information and the historical information of its sources is being developed using the CIDOC Conceptual Reference Model (“CRM”) ontology. Based on the conceptual model, a database with the scenario’s and bibliography’s historical information is created on Protégé. Through SPARQL queries a user will be able to retrieve the historical information stored in the database.