Centrality as a process: Accounting for attraction inequalities in deformed grids

The 'centre' of a settlement, whether city, town or village, usually means a concentration and mix of land uses and activities in a prominent location. At any point in time, it is usually fairly clear where the centre is and what its limits are. However, the need to revitalize the centres of towns and cities, has drawn attention to how little we know of the processes by which centres are generated and sustained. Historically, it is clear that centres not only grow and shrink, but also shift and diversify, and with growth to large town or city level, a whole hierarchy of centres and subcentres usually appears diffused throughout the settlement. The challenge is to understand centrality as a process, rather than to describe it as a state. In this paper it is proposed that well-defined spatial factors first play a critical role in the formation and location of centres, and then play an equally critical role in developing and sustaining their vitality. The process works through the impact of spatial configuration on movement, and the subsequent influence this has on land use choices, and the development of the area as an 'attractor' in the settlement layout as a whole. A proper understanding of these spatial factors and the processes they set in train is, it is argued, vital to any programme for the revitalization, sustaining or long-term development of centres.