Central Place Theory

Central place theory, developed by the German geographer Walter Christaller as his doctoral dissertation, Central Places in Southern Germany in 1933, was a highly influential set of models widely used to describe and analyze urban hierarchies in the mid 20th century.

Essentially, central place theory is a model of city systems that posits them as retail centers (central places) that distribute goods and services to their surrounding hinterlands. Like many models of spatial analysis, it assumes a featureless isotropic plain in which population density and transport costs are equal in all directions. Each good has a threshold, or minimum market size, as well as a range, or maximum distance consumers will travel to purchase it (Figure 1). The size of a given good's range and threshold vary with transportation costs, or the friction of distance, as well as the willingness of consumers to travel to obtain a given good or service. As the effective price increases with distance from the central place, demand declines accordingly. The model is thus compatible with the neoclassical views of economics that privilege consumer demand in the analysis of social and spatial structures.

Different goods and services have different thresholds: inexpensive, frequently purchased, and everyday necessities have low thresholds (e.g., convenience stores, groceries, eating and drinking establishments, dry cleaners, and other personal services), while costly, infrequently used goods and services, including luxuries, have much larger ones (e.g., jewelry, specialized medical services). The degree of specialization of a good or service is thus directly proportionate to the willingness of consumers to travel to obtain it: Increasingly specialized products attract consumers from progressively longer distances. A hierarchy of goods and services leads to a hierarchy of central places to distribute them. Central place theory thus ranks urban places on the basis of their ability to distribute goods that range from “low-order” to “high-order” ones. The order of a central place is determined by the highest-order goods that it distributes to consumers around it.

Figure 1 Range and threshold. In central place theory, each good has a minimum market size (threshold) and a maximum distance (range) that consumers will travel to purchase it.

Source: Ingolf K. Vogeler, University of Wisconsin–Eau Claire, http://www.uwec.edu/Geography/Ivogeler/w111/urban1.htm.

The resulting hierarchy of central places—the urban hierarchy—reflects the imperatives of market forces over space, which tend to maximize the number of centers, maximize the number of consumers served, and minimize the aggregate distances that consumers must travel to [Page 381]purchase goods of varying levels of specialization. Large cities distribute both low- and high-order goods, the latter over increasingly large hinterlands. Higher-order centers are more widely spaced, with larger populations, serve large market areas, and are encountered less frequently on the landscape. Thus, metropolitan areas, the highest order, offer the greatest diversity of goods and services and hinterlands that extend over vast distances. Conversely, progressively lower-order centers are nested within the market areas of higher-order centers. Small, rural hamlets, for example, historically formed central places serving low-density agricultural regions. Progressing up the urban hierarchy, one encountered increasingly larger but infrequent places with a mounting diversity of goods and services.

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