Significant cities beyond the metropolises? Regiopolises and their role in the German urban system

Regiopolises and regiopolitan regions are receiving unprece-dented attention in German spatial planning policy. In addi-tion to the promotion of the German RegioPole network by the federal government, regiopolises and regiopolitan regions are already designated in several spatial development plans. In the academic discourse, however, regiopolises are hardly taken up. This is particularly evident in the fact that dimen-sions such as city size (more than 100,000 inhabitants) and spatial location (outside metropolitan regions) are used to empirically identify regiopolises as such. A specific function-ality or a specific significance in the German urban system, however, is only hinted at, following the established spatial planning concepts of metropolitan regions and central places. Against this background, this paper examines the question of what constitutes a regional centre or region in terms of its specific functionality and what significance it has in the urban system. The international discourses on second-tires-cities, borrowed size and agglomeration shadow are also taken up.