Functional Polycentricity: Examining Metropolitan Spatial Structure through the Connectivity of Urban Sub-centres

A shift from monocentric cities to increasingly polycentric urban regions has been widely recognised in recent research literature. Although polycentricity in general refers to the existence of several adjacent centres within the same area, many studies have emphasised that functional linkages between the centres of an urban system are also an essential part of polycentricity. Despite the increasing number of studies concerning functional polycentricity, research on the subject is still in a development phase. In this paper, a new approach to measure functional polycentricity is presented, in which functional polycentricity is approached through the connectivity of individual centres to the whole urban system. The paper illustrates the potential of the method with empirical case studies addressing the urban spatial structures of three functional urban regions in Finland. In the case studies, detailed commuting data are used in order to measure the degree of functional polycentricity.