Walter Christaller proposed his Central Place Theory in 1933. He aimed to rationalize the distribution of cities over geographic space. He was concerned with the way the settlement of different sizes evolve and are spaced out. It is a theoretical account of size and distribution of settlements within an urban system where marketing is predominant urban function.
Basic Idea Behind Central Place Theory
- Christaller’s theory is based on the study of Bavaria region of Germany.
- There is a hierarchy of settlements in urban system.
- Metro cities are placed at apex.
- Each city of higher order is surrounded by many cities of lower order. So, the number of cities increase as we move from apex to the lower order.
- The functions of higher and lower order cities are different.
- This theory has theoretical elements of both Primate City and Rank Size Rule.
- Isotropic Plain: This means that the cities are located in an homogenous plain area without topographic undulations.
- The population is distributed evenly over this space.
- All of population demands the same goods e.g. clothing, healthcare etc.
- Distance decay: The people tend to fulfil their needs from the nearest city possible. So, there is distance decay in context of interaction of people with a certain city.
- Identical Income: The income of the consumers is identical i.e. all consumers have similar purchasing power.
- The cities are arranged in triangular lattice i.e. cities are distributed perfectly evenly over space (see Fig.1).
Central Place Theory is based on four key concept
- Threshold: It means that the minimum volume of business a firm will need to be able to operate economically. It shows the amount of business need for the viability of a business (Blue area in Fig.2).
- Complementary Area: The city serves additional area over and above the threshold area. This additional area is called complementary area (Orange area in Fig. 2).
- Range of Goods: Range of goods means that maximum distance from which a consumer is ready to travel to the city for purchasing a good. Greater range of good means that people from farther places are ready to travel to city for purchasing a good and vice-versa. The outer boundary of complementary area denotes the range of goods.
- Central goods and services: Certain goods and services can only be provided by larger cities only. This means that people from smaller cities and towns must travel to large city for purchase of a central good. For example, for a heart surgery, people have to travel to large cities.
Two Key Principles of Central Place Theory
- Principle of Centralization: All matter in the universe has a core i.e. tissues has nucleus, earth has core etc. It signifies relationship between central place and its periphery.
- Principle of Hierarchy: It means that most phenomena in the universe is arranged in certain hierarchy. For example, satellites, planets, stars, galaxies etc. are arranged in universe in certain hierarchy. Similarly, cities have hierarchy.
Working of Theory
As assumed, the settlements are equidistant on an isotropic plain.
These settlements will serve a circular area around them but in this case there is an area which remains unserved between these circular areas (See Fig. 3). To solve this problem, Christaller overlapped these area which led to problem of overlapping range of goods. He divided this overlapped area into half and came up with hexagonal pattern. Hexagons fit perfectly into each other (Fig. 3).
As seen in Fig. 4, the apex central place has six cities of second order located at the nodes of the hexagons around it. Similarly, cities of second order has cities of third order located at the nodes of hexagons. One must notice that the size of cities may vary but they are still located in a triangular lattice.
Principles of Arrangement and Numbering of Cities
Christaller formulated three principles to study the hierarchical spatial structure of urban system.
1. Marketing Principle (K = 3)
Cities have certain central function and serve the area around it. According to this principle, the cities are located at hexagonal node. This principle states that each city serves one third of three complimentary areas of three lower order cities.
K = 1 +(1/3 * 6) = 3
Therefore, the number of cities at each lower hierarchy will be three times more than the preceding order of cities. The number of cities will be like 1, 2, 6, 18, 54, 162…. and so on.
2. Transport Principle (K = 4)
This principle offers to provide the most efficient and quick route between different cities. It states that the cities will be located in the middle of each side of hexagons rather than nodes. Therefore, each city will serve the complimentary area of two of the lower order cities.
K = 1 +(1/2 * 6) = 4
The number of cities at each lower order will be three four times the number of preceding order or cities. The number of cities will be like 1, 2, 8, 32, 128…. and so on.
3. Administrative Principle (K = 7)
This principle states that each higher order city will serve the administrative needs of all the peripheral cities of lower order along with its own needs.
K = 1 +(1/1 * 6) = 7
The number of each subsequent order of cities will be seven times the number of preceding order of cities. the number of cities will be like 1, 6, 42, 294… and so on.
The readers should understand that these principles can not be applied alongside each other. We use these principles individually to understand urban landscape.
Christaller’s theory explains the distribution of cities of different size over space and their relationship with each other though different principles. The theory reflects the real world situation of arrangement of cities of different sizes but not with perfection. For example, Delhi NCR is central city with many lower order cities surrounding it like Panipat, Sonipat, Meerut etc. Though, this theory has many deficiencies but it has merit in real world application.
Kulwinder Singh is an alumni of Jawaharlal Nehru University, New Delhi and working as Assistant Professor of Geography at Pt. C.L.S. Government College, Kurukshetra University. He is a passionate teacher and avid learner.