Relics of the road network suburbs of Toruń from the late 18th century in contemporary topography of the city based on GIS analysis

Abstract

The article presents research that aimed to identify the remains of the road network of Toruń’s close suburbs from the late 18th century on the contemporary system of city streets based on GIS (Geographic Information Systems) analysis. The study area included the close suburbs of the Old Town of Toruń. The source materials were two plans of Toruń and its suburbs from the late 18th century and a contemporary geodetic plan of the town. The historical plans did not meet cartometric requirements. Therefore, an essential condition for achieving the objective of the study was to make them precisely match the contemporary geodetic plan of the town (constituting the reference layer). For this purpose, a rubber sheeting type transformation was applied, which increased the cartometric value of the analysed plans and enabled the authors to acquire qualitative and quantitative data from them. In addition, a certain margin of error was assumed in the potential compatibility of the course of the contemporary streets of Toruń in relation to the roads of suburbs of the 18th century town, which was realized based on the buffer function. The results of the analysis show that the contemporary streets of the close suburbs of the Old Town of Toruń correspond to approximately 40% of the length of roads from the late 18th century, as depicted on the analysed plans. In the authors’ opinion, in the contemporary topography of the close suburbs of the Old Town of Toruń, many streets or their sections can be considered the remains of the course of the 18th-century roads with a high probability, and even, which results from historians’ research, the course of medieval ones. This is despite centuries of transformation of the town’s suburbs that were related primarily to the construction of fortifications from the 17th to the 19th century.