Central Places in Urban Areas

The spatial organization of cities tends to follow a central places structure as the goal is to provide services to the whole population. In this case the central places are not whole urban areas, as in the standard representation of central places, but specific nodes where commercial and service activities are concentrated. The above example depicts an hypothetical concentric multi-nodal city with a ring road. Many metropolitan areas in North America, Europe and Asia have such a spatial structure, but with significant variations in density, modal preferences and spatial extension. The Central Business District (CBD) has the highest order and represents the "central place" of an urban area, followed by centers of lesser importance, up to local centers offering basic services including groceries, banking and entertainment. The whole spatial organization is structured by transport axis radiating from the CBD. Increased mobility, namely the automobile, has substantially reduced the cohesion of urban areas and their service hierarchies.