The paper describes the research and creation of the map of the Diocese of Varaždin. After many changes in the Diocese over the years, this map has finally been completed and published for the first time. The process of the map making is described. Furthermore, it points at the problems related to some specific contents of the map and provides solutions to those problems, specifically, the divergence of the borders gathered from different sources. This extensive project resulted in the creation of a map in A2 paper format on a 1:225,000 scale. The GIS and the data collected about the specific map content were both the starting point and the source of data for the visualization of the map of the Diocese of Varaždin. This is important because there are none that precede it. Such a thematic map would therefore mark an advance in the field and be appropriate. ARTICLE HISTORY