A presentation given by Keith May and me at CAA 2004 held in Prato, Italy. The topic was a sub-project which emerged from the English Heritage Revelation project; the Ontological Modelling project. This project looked at a range of existing data models, paper forms, databases and other source information and through discussions with domain specialists, created a representation of the information archaeologists use based on the CIDOC Conceptual Reference Model (CRM).