Central Place Theory is a theory describing how cities emerge and are formed. It looks at two principles: the threshold principle (population size and wealth) and transport principle (willingness of people to travel to access goods).
The theory was devised by the German geographer Walter Christaller (1893 – 1969) in 1933.
Christaller believed that even though there is no masterplan that governs where and how urban settlements come up, there is an inherent logic which dictates why cities come up where they do, and why they attain the size that they do.
Central Place Theory – What you Need to Know
1. The Theory has Two Principles
Central place theory is based on two principles:
- Threshold or the Marketing Principle – A city will come up where there is a concentration of a population that is either numerous enough or wealthy enough for the development of a market that offers a wide range of goods and services.
- Range or the Transport Principle – The geographical extent of the size of the city will be determined by how far the population of the city is willing to travel to avail of the said goods and services.
These principles explain several features of urban and rural geography, such as why larger cities tend to be spread farther apart, whereas smaller towns or settlements tend to be clustered closer together.
2. The Theory Believes Cities Naturally take Hexagonal Shapes
Christaller then went on to devise a geometrical model to depict how cities would be arranged on a geographical plane. According to this model, cities and settlements would come up in a hexagonal (or triangular) lattice-like pattern on a landscape.
This is because a hexagon is the most efficient arrangement for organizing objects within a given space causing least wastage.
This mathematical fact called the Honeycomb Conjecture has been known to mankind since antiquity but was decisively proved only in 1999 by the American mathematician Thomas C. Hales. (Hales, 2001).
It is frequently encountered in nature where honeybees build their honeycombs in a hexagonal pattern, and is followed by the packaging industry, where hexagonal packing is preferred as it is known to minimize wastage of space (Chamberland, 2015).
In the case of cities and villages, this means that a city or a market place can cater most efficiently to the smaller towns or the rural settlements that surround it only if they are arranged in a hexagonal arrangement with the city or marketplace at the centre, and the smaller settlements arranged around it in a hexagonal lattice-like pattern.
Since a hexagon is made up of six congruent equilateral triangles, the triangular arrangement would also suffice in place of a hexagon.
Any other pattern of arrangement would be inefficient in terms of the area served by the central place (or access of the node to the central place) and the transport costs of commuting to the central place, and thus, in the long run, would prove to be unsustainable.
3. The Theory Can Predict City Size and Shape
Based on this theory, Christaller went on to make certain predictions about how cities and settlements would be arranged on a physical landscape.
These predictions are based on what are called K-values, where K gives a measure of how much of the area of its surrounding settlements would the central place take up.
So, K = 3 means that the market area of the central place would take up one-third of the market area of each of the surrounding smaller setlltlements called nodes. Or in other words, the central place is three times the size of the smaller market settlements that adjoin it.
K can have different values based on different variables, with 4 and 7 being the most common in addition to 3.
Alternative Theory: Concentric Zone Model
Central Place Theory Examples
1. Polders of Netherlands
Polders are low lying areas that have been reclaimed from the sea or other water bodies and made suitable for human habitation by fortifying them with dikes and embankments which keep the water at bay.
Since large parts of Netherlands are situated below the sea level, much of its land area consists of Polders that have been reclaimed from the sea.
These Polder settlements came up in accordance with the layout predicted by the Central Place Theory.
The most well known examples of these are IJsselmeerpolder and Noordoostpolder whose layout is in accordance with the Central Place Theory (Sugiura, 2006).
2. Fens of East Anglia
Like the Dutch Polders, the Fens of East Anglia in England are low-lying regions of marshy land that were drained centuries ago to make way for human habitation.
The land in the Fens is fertile and hence supports a large number of settlements, most of which have sprung up in accordance with the tenets of the Central Place Theory, which is to say, a honeycomb like layout of large market towns surrounded by smaller towns in a triangular or hexagonal pattern.
3. The American Midwest
The American Midwest is a vast flatland of agricultural hinterland interspersed by small towns and the occasional large industrial city.
The Midwest is called America’s breadbasket on account of its disproportionately large share in America’s agricultural output.
C.J. Galpin (1864 – 1947), a sociologist at the University of Wisconsin, studied the geographical layout of the various rural communities, small towns, and the large cities of the American Midwest and discovered that they are laid out in a series of rough hexagonal patterns as outlined by the Central Place Theory.
Galpin concluded that for a market town offering goods and services to equitably serve all the farming communities that surrounded it, there would need to be six farming communities surrounding each such market town (Galpin, 1916).
Further these smaller market towns would in turn form a hexagonal pattern relative to a larger city offering higher order services, and so on, until the largest Central Place offering the highest order goods and services and supporting the largest density of population were to be reached.
In the case of the American Midwest, these would be the industrial hubs of Chicago, Detroit, and Kansas.
Like the American Midwest, Saskatchewan in South-western Canada is a flat prairie grassland which is called the breadbasket of Canada on account of its high agricultural output.
Stabler and Olfert (2002) have traced the development of Saskatchewan’s urban and rural communities to the postulates of the Central Place Theory.
Regina and Saskatoon are the only two major cities in the province, while a number of smaller market towns serve the agrarian communities of the province organized in a hexagonal layout.
Central Place Theory Strengths and Weaknesses
1. It Explains the Hierarchization of Urban Centres
The Central Place Theory does the best job among all theories of spatial geography in explaining why some cities are larger than others.
Drawing upon the threshold and the marketing principle, the Central Place Theory explains how the size of an urban settlement is decided by consumer preferences.
Large cities are the ones offering higher order goods and services such as jewelry, electronics, shopping malls, whereas smaller settlements offer lower order goods such as grocery, household items, etc.
Larger cities tend to be spaced farther apart, whereas smaller marketplaces are clustered closer together. All of them are then organized in a hexagonal (or triangular) lattice like structure to serve the maximum area of the hinterland.
2. Can Be Integrated with Other Spatial Models to Explain a Diverse Range of Phenomena
Central Place Theory (CPT) can be integrated with spatial interaction models (SIM) to explain a number of urban geographical phenomena.
For instance, Openshaw and Veneris (2003) applied CPT to the distribution of medical care facilities in urban centres. They describe how medical facilities are arranged spatially in a hierarchy, much like the one CPT describes for urban settlements. Through their research, they show how the development of medical care facilities is determined by the marketing and the transport principle as outlined by the CPT.
Thus higher order medical care is available in areas with larger populations (threshold or marketing principle) and which are within easy reach of a sizeable number of the population (range or transport principle).
1. Makes a Large Number of Assumptions
Central Place Theory is based on a large number of assumptions such as:
- The areas under study are completely flat and limitless.
- The population is evenly distributed in the area under consideration.
- The consumers have similar purchasing powers.
- All the settlements are equidistant from each other.
Such assumptions in effect mean that the theory remains an abstract formulation and can rarely be applied accurately to real world situations.
2. Agriculture Centric
As can be seen from the list of examples given in the previous sections, the Central Place Theory is best applicable to large rural-agrarian hinterlands with a handful of market towns located within that hinterland.
Its applicability to industrial cities or modern urban spaces based on a service sector economy is severely restricted.
3. Poor Adaptability to Change
Central Place Theory was devised in the early decades of the 20th century – a time of rapid, and relatively new urbanization. Most of the world’s population still lived in villages and cities were home only to a small elite.
Cities and villages have evolved dtrastically since then, but the Central Place Theory has not been able to evolve to explain these changes.
For instance, in the 21st century, the world is increasingly moving online and goods and servies are exchanged without the need for a physical marketplace. Some of the biggest marketplaces today such as Amazon and Etsy are exclusively online stores with no physical presence.
In the absence of a physical space itself in which to situate marketplaces and economic activity, the Central Place Theory, being a theory of physical and spatial geography, draws a complete blank.
Related Theory in Human Geography: Environmental Determinism Theory
Central Place Theory is a theory that attempts to explain the spatial distribution of urban settlements. The theory has been found to be useful in explaining the distribution of rural market towns
However, the applicability of the theory is somewhat limited, as it does not take into account modern phenomena such as online marketplaces. In addition, the theory makes a number of assumptions which may not hold true in real-world situations.
Overall, Central Place Theory is a helpful tool in understanding the distribution of urban settlements, but should not be used as the sole explanation for this phenomenon.
Chamberlad, M. (July 2015). The Miraculous Space Efficiency of Honeycomb Slate. Retrieved from: https://slate.com/technology/2015/07/hexagons-are-the-most-scientifically-efficient-packing-shape-as-bee-honeycomb-proves.html
Hales, Thomas C. (2001). The Honeycomb Conjecture. Discrete and Computational Geometry, 25 (1), 1–22. Doi: https://doi.org/10.1007/s004540010071
Galpin, C. J. (1915). The social anatomy of an agricultural community. Agricultural Experiment Station of the University of Wisconsin Research Bulletin 34.
Openshaw S. & Veneris Y. (2003). Numerical experiments with central place theory and spatial interaction modelling Environment and Planning, 35(8), 1389–1403. Doi: https://doi.org/10.1068%2Fa35295b
Stabler, J.C. & Olfert, M.R. (2002). Saskatchewan’s Communities in the 21st Century: From Places to Regions (Canadian Plains Reports) Canadian Plains Research Center.
Sugiura, Y. (2006). Planning on Settlement Location in the IJsselmeerpolders and Central Place Theory Geogrpahical Review of Japan, 79 (11), 566-587.
Dr. Chris Drew is the founder of the Helpful Professor. He holds a PhD in education and has published over 20 articles in scholarly journals. He is the former editor of the Journal of Learning Development in Higher Education. [Image Descriptor: Photo of Chris]