Central Places in Urban Areas
The spatial organization of cities tends to follow a
structure as the goal is to provide a hierarchy of services to the whole urban population.
This is particularly the case when looking at large metropolitan
areas composed of a variety of nodes where
commercial and service activities are concentrated. It is assumed
that the hierarchy observed at the regional level will also have
a correspondence within a metropolitan area. The above example
depicts a 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.
Still, although more diffuse, this hierarchy remains present.