Abstract
Street names have long been of scholarly interest, yet their regional variation remains surprisingly underexplored, despite several compelling reasons to expect its presence. This article presents findings from a study of the regional differentiation in the structure of street names across Poland’s administrative regions (voivodeships). Drawing on data from the TERYT register, the names were cleaned, coded, and subjected to quantitative analysis using similarity measures and hierarchical clustering methods. The results reveal that all voivodeships exhibit a similarly high degree of internal unevenness in their street name structures, and –except in the case of geographical and topographical names –demonstrate a generally high level of inter-regional similarity. For both the full set of street names and the subset of geographical-topographical names, the analysis identified spatially coherent groupings of voivodeships with comparable naming structures. These groupings closely reflect the patterns of historical (relict) boundaries and the configuration of major physiographic regions.