3D Digital Modelling of a Historic City: Methodology of Reconstructing an Image of a City Based on the Case Study of the City of Poznań

Abstract. Poznań is a relatively unique case of a city where the central area was significantly recomposed during the past two centuries. Its current shape has lost nearly all of its original, historically formed character. Such far-reaching changes have blurred the image of Poznań’s past and its specific landscape. The effect of such a development process of the urban space is incomplete knowledge of the city’s historic appearance. Taking into account the above premises, the authors developed a digital twin of the city in the late 18th century, which recreates its historic image. The topic of digital twins of cities is often discussed, however the reconstruction of a digital historic city is quite rare. The main difficulty in this respect is the lack of a clear methodology of working on a reconstruction model, as well gaps in obtaining detailed historic data and lack of access to source materials. The paper discusses the methodology of constructing a digital twin of the historic city of Poznań. The authors present their original method for recreating a specific spatial layout based on analyses of hydrological and natural environments. The key element is the analysis of available sources, the choice and examination of which is presented in the paper.