cost between similar types of goods is the additional transport cost associated with
traveling a greater distance to obtain the good, a concept linked todistance decay.
That is, each good or service offered at a location on the plain would have a spe-
cificrange, or distance that consumers would be willing to travel to procure the
good or service. More expensive goods or services that would be purchased less
frequently, which Christaller called “higher-order” goods and services, would
have a larger range than so-called “lower-order” goods and services that would
be cheaper and purchased on a regular and frequent basis. For example, a higher-
order good might be a diamond ring; a lower-order good would be a bottle of milk.
This would result in the formation of a specific hinterland in the shape of a circle
for each good or service, extending outward from the place it was offered. The
radius of the circle would equal the range of the particular good or service. Any
consumers located beyond theboundariesof this hinterland would not travel to
the place to obtain the good or service, as the transport cost would exceed the
value of the good or service.
Each type of good or service offered at locations on the plain would have a spe-
cificthreshold. The threshold is the minimum number of consumers necessary to
offer the good or service at that location. This can be represented by an area,
because the theory assumes that the population is uniformly distributed across
the space of the plain. Higher-order goods will have much larger thresholds,
because they are goods or services that are only purchased infrequently, but
lower-order goods or services will have much lower thresholds, due to the higher
demand for them. This can be easily visualized by using the examples provided
above—one may purchase milk on a weekly basis, but a diamond ring only once
in a lifetime. A jewelry store requires a much higher threshold (number of con-
sumers) than a supermarket. The resultof this system is that the plain now is
covered by imaginary circles radiating outward from central locations, each sym-
bolizing the hinterland of a type of good at that location. This means, however,
that some spaces will remain between the hinterlands, since circles do not fit
tightly together. Central Place Theory suggests that the hinterlands are not circu-
lar, but rather take the shape of hexagonsthat then follow a beehive pattern cover-
ing all of the space of the plain. Furthermore, there exists a hierarchical ordering
of the hexagonal pattern, based on the varying sizes of hinterlands. Central places
offering the highest order goods and services will have the largest hexagonal
hinterlands. For lower-order goods and services, these large hinterlands will be
subdivided into a series of smaller hexagons, representing the next order of goods
and services, offered at smaller central places. The number of hexagon sequences
in the hierarchy is dependent on the total number of different orders of goods
available on the plain.54 Central Place Theory