This paper analyses the geographical features and potential of memorial tourism development in the tourism region of Istria in Croatia. In the past century, Istria has had several political and socio-economic turning points, with far-reaching consequences for its overall development. For the most part, the historical turning points in the 20th century in Istria were marked by armed conflict, followed by individual and mass human casualties, terror, and the persecution of the population. The motive of travel in memorial tourism here is to visit the places where these tragic events occurred. Therefore, the aim of this research was to determine the geographical distribution of potential sites in Istria suitable for the development of memorial tourism. An additional objective was to propose thematic routes of memorial tourism in the areas of Istrian towns and municipalities. A secondary aim of this research was to provide a geographical contribution to the scientific evaluation of memorial tourism in Croatian tourism regions, with proposals for measures in the planning of the development of this form of tourism.