Central Place Theory

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Central Place Theory

• This is theory concerned with the functional
  importance of places

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Central Place

• -is a settlement that provides goods services.
  It can be small (a village) or large (primate
  city)
• ? all settlements form a link in a hierarchy

London 7m
Peterborough 156,000
Norwich 122,000
Cambridge 108,000
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Why are there very few large settlements?
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Settlement hierarchy

• Why are there very few large settlements?
• Large settlements need a very large population
  (threshold) to support all of their functions
  (services)
• Large settlements provide very high order
  functions (Great Ormond St, Houses of
  Parliament). Because these functions are so
  highly specialised there is not enough
• demand to support more than a few of them

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Sphere of influence

• Is the area around each settlement that comes
  under its economic, social political control.

Cambridge
Luton
Reading
London 7m
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Sphere of influence

• The extent of the sphere of influence will depend
  upon the spacing size functions of the
  surrounding central places

Norwich
Cambridge
Luton
Reading
London
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Central place functions
Function a service

• These are the goods services it provides for
  local customers for clients drawn from its
  wider sphere of influence

Luton
Cambridge
Reading
London
Population size does not necessarily determine
the importance of the central place
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Range Threshold
Threshold
Range (km)

• The range of a good or services is the maximum
  distance that people are prepared to travel in
  order to obtain it. (short distances for a low
  order item e.g. newspaper)
• The threshold of a good or services is the
  minimum number of people required to support it
  i.e. 2500- doctors surgery
• 500-primary school/ 25,000-shoe shop 60,000 for a
  large supermarket/
• 100,000- large department store/ 1million
  University
• The more specialised the service the greater the
  number of people needed to make it profitable.

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Range Threshold

• Low order items (basic items) newspaper
• High order items (specialised items) furniture
• Low order functions (basic services) corner
  shop/ Primary school
• High order functions (specialised services)
  university/ hospital
• Settlements providing low order services low
  order settlements (rural)
• Settlements providing high order services high
  order settlements (urban)

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Changes in population size number of functions

• Settlement sizes change over time (via births,
  deaths, migration)

• Settlement functions (services) change over time
• Over the past 50yrs in the UK decrease in the
  no of services available in small settlements
  and an increase in the no of services provided
  by larger settlements

1998
1940
Number of functions
Settlement size- increases
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Factors that affect a settlements number of
functions

• Settlement depopulation or increased population
• Greater wealth mobility means some rural
  populations no longer visit their own local
  services but go further afield seeking services
  from higher order settlements
• Domestic changes (deep freezers) means rural
  household, no longer make use of daily low order
  services (village shop)

Population size does not necessarily determine
the importance of the central place? but there is
a strong correlation
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The rules of functional hierarchies
(service)

• 1. The larger the settlements are in size, the
  fewer in number they will be
• 2. The larger the settlements grow in size the
  greater the distance between them
• 3. As a settlement increases in size the range
  and number of its functions will increase
• 4. As a settlement increases in size, the number
  of higher-order services will also increase (the
  services become more specialised)

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Walter Christallers model of central places

• The theory states that threshold and range act as
  laws that govern the number, size and
  distribution of settlements
• When these 2 factors act together they create a
  hierarchical landscape
• Christaller noticed in the flat land of South
  Germany that towns of a certain size were roughly
  equidistant (uniformly spread)
• He stated that the ideal shape for each towns
  sphere of influence should be a hexagon because
  circles either leave gaps (which are unserved by
  any central place) or they overlap (meaning one
  area is served by too many central places)

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Christaller's central place theory

• Christaller stated that the best shape for a
  sphere of influence is a hexagon. This shape
  means that consumers still have accessibility to
  the highest order central place and its trading
  area from all parts of the hexagon.
• Christaller's key idea was that customers would
  go to the nearest higher order central place to
  buy goods and services
• High order central places act like a magnet for
  consumers.
• He called this phenomenon K3 (or the marketing
  principle)
• In order to make his theory work Christaller had
  to make a few assumptions
• He assumed that each trading area had an
  isotropic surface (that the whole area was the
  same all over) i.e.
• ? the whole area was flat
• ? there was only 1 form of transport (and
  transport costs were proportional to distance)
• ? the population was distributed evenly across
  the plain

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What's wrong with circles?
Whats wrong with circles
Source http//www.uwec.edu/bfoust/155/G155_RS3/sl
d002.htm
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The areas within the black dots shows the sphere
of influence (trading area) of the largest
settlements
?Like London
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K3 The marketing principle
Example -the highlighted lower order settlement
(village X) will have 1/3 of is consumers go to
the city (settlement A) and 1/3 will go to town Y
and 1/3 will go to town Z (middle order
settlements) All the other lower order
settlements (red dots) will follow the same
pattern.
The high order (3rd order) settlement (A) in the
middle is surrounded by medium order settlements
(black dots) and lower order settlements (small
red dots). These consumers are attracted in
equal amounts to whichever large central place is
nearby.
Y
Settlement X
Z
Why is K3 called K3? Hint? look at the numbers
of consumers who visit the highest order
settlement
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K4 The Traffic Principle
In the K4 model the lower order settlements (red
dots) only have a choice of 2 higher order
settlements to visit, in order to buy goods and
services. -Half of them go to settlement A and
the other half go to a medium order settlement
(black dot)
How did K4 get its name?
Why is K4 called the Traffic Principle (model)
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How the K4 Traffic principle got its name
The K4 model is called the traffic principle
because the model shows how consumers are
influenced in where they go to shop for goods and
services by transport routes
The Crossways train-line
In this example the low order settlements (red
dots) are located along a transport route. This
means that these low order villages can only
visit other settlements that are also on their
transport route. So they are limited to visiting
the settlement behind them on the transport route
or the settlement in front of them.
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This model shows a hierarchy of control? -Lower
level settlements are arranged within the sphere
of influence of the highest order settlement.
This is done so that the lower order settlements
can be completely controlled by higher levels.
K7 The Administrative Principle
A high order central place is shown. -All the low
order settlements lie within the hexagonal trade
area (U,V,W,X,Y)
U
Z
V
Y
Why is K7 called K7?
X
W
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The uses of Christallers central place model

• The model is often used by governments to plan
  the location of new towns (i.e. Milton Keynes)
  and high order services i.e. hospitals
• It is used by transport authorities to plan
  transport routes( so that all areas have equal
  access i.e. K4 model)
• Businesses can use the model to decide where to
  locate a new shop

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Limitations of Christaller's model

• Few real-life regions fit Christaller's model
  (except the flat lands of the Dutch Polders and
  East Anglia in the UK)
• The problem lies in the basic assumptions of the
  model
• People do not always go to the nearest central
  place (they may chose a new edge of city
  superstore further away) So the K3 theory
  wouldnt work.
• Large areas of flat land rarely exist. Mountains
  hills etc distort transport routes (so the K4
  theory wouldnt work)
• People and wealth are not evenly distributed (if
  poorer people live in a certain area their
  nearest high order settlement is expensive then
  they wont visit it)
• Governments often control where new towns are
  located, not market forces (i.e. not necessarily
  where the demand for goods and services is
  highest)

Hill
Train-line