26th International Cartographic Conference, August 25 – 30, 2013, Dresden, Germany A formal ontology for historical maps Eleni Gkadolou*, Emmanuel Stefanakis** * Department of Geography, Harokopio University of Athens ** Department of Geography, Harokopio University of Athens, Department of Geodesy and Geomatics Engineering, University of New Brunswick Abstract. Historical maps are a major component of our scientific and cultural heritage collections. Apart from the aesthetic value of the artifacts, maps also deliver valuable historical and geographic information. In order to use the historical cartographic information effectively, the semantic documentation of maps becomes a necessity and ontologies are suggested to achieve this. This paper examines how the top level ontology CIDOC- CRM “handles” historical maps and presents a formal description of the “Carte de la nouvelle frontière Turco-Grecque”, a map attached to the Con- vention of Constantinople that set the borderlines between Greece and Ot- toman Empire in 1881. Keywords: CIDOC-CRM, historical map, ontology 1. Introduction Maps are the graphical representation of geographical space and spatial phenomena. Historical maps are a valuable source of historical information since they actually document the spatiotemporal evolution of entities. In order to use the historical cartographic information effectively, the seman- tic documentation of maps becomes a necessity. The semantic definition of a map restores any semantic ambiguities. In addition structures the rela- tionship between historical and current geographical space. As a result: a) the correlation between an entity’s spatiotemporal changes and their causes is explicitly attributed, b) semantic search of geospatial data on the web using spatial and conceptual criteria (for example based on toponymy or geometry) is possible and c) the development of interoperability mecha- nisms in several web – spatial or not – applications that use maps is facili- tated. Ontologies could be used to achieve these goals. Furthermore, historical maps are a major component of our scientific and cultural heritage collections. The use of ontologies to document cultural