Great Cities
• Asia-Tokyo-Yokohama, Osaka-Kobe-Kyoto
• Mega Cities:
• UN says by 2025 at least 15 cities will be over 20
million
– Many of the world’s most populous cities are found in
the poorest nations-Mexico City, Shanghai, Calcutta,
Mumbai & Cairo
– Close are Bangkok, Indonesia; Lima-Callao, Peru;
Saigon-Cholon, Vietnam
– Mexico City, Sao Paulo and Shanghai will have over 30
million by 2025
Pull Factors
• Pull factors often more imaginary that real-esp. in
less developed areas.
• 1990s Africa had the fastest growing cities in the
world-followed by South Asia, East Asia, South and
Middle America.
• Cities of North America, Southern South America,
Australia grew more slowly
• Western Europe’s cities grew very little if at all.
• New York was the world’s largest city for many
years-now overtaken by Tokyo-Mexico City will
overtake Tokyo-by 2025 NYC will not be in top 10.
Urban Problems
• Zoning laws are lacking
in many poor countries
• Squatters occupy any
open space on the
outskirts of the city
• Sharp contrast between
fancy hotels of downtown
and slums on outskirts
• Cairo for example-paved
streets give way to dusty
alleys, tenements, traffic,
garbage & 12.5 m. people
bursting at the seams
• Many cities in
developing nations are
growing at a rapid rate
with many new arrivals
each day.
• Unofficial suburbs such
as this favela of Rio de
Janeiro are poor and
often lack basic
services. (Disamenity
sector)
• Clinging to a hillside,
this neighborhood often
suffers fatal landslides
during heavy rains.
Rank-Size Rule
• The larger the city-the fewer there are• Model indicates that the population of a city or town in
inversely proportional (the fraction) to its rank in the
hierarchy
• If largest city is 12 million then 2nd largest is 6 m. (1/2) 3rd
largest is 4 m. (2/3) 4th largest is 3 m. or (3/4) 10th largest
is 1.2 million
Rank-Size Rule does
Not apply to
primate
Cities such as Paris,
Mexico City and so
forth
Urban Function
• Every city or town has an economic base.
• Basic sector-workers who produce goods for export or
local consumption
• Non Basic sector or Service sector-workers who
maintain the city, work in offices and provide services
for others
• The number of Non basic sector workers is always
greater than Basic sector workers-as cities increase in
size the ratio increases
• Most large cities have a ratio of 1 to 2
• Multiplier Effect-if a business adds 50 manufacturing
jobs-another 100 non-basic workers will be added to
the work force
Functional Specialization
• A dominant service or industry was found in many
cities during the Industrial Revolution.
• Chauncy Harris wrote “A Functional Classification of
Cities in the United States” in 1943-in it he described
the concentration of manufacturing cities in the
Northeast with functional specialization and the wide
diversity of western cities with no dominant function
• e.g. Detroit-automobiles, Pittsburgh-steel
• Las Vegas and Atlantic City gambling
• Leadville, Colorado-mining
• Vero Beach, Florida-resorts
• Trend today is toward diversity-especially in the
Rustbelt.
Central Place Theory
• Central Places-hierarchy is based on population, function
& services.
• Economic reach-how functions & services attract
customers from areas beyond the urban limits.
• Centrality-the central position & ability to attract
customers to a village, town or city.
• Range of Sale-the distance people are willing to travel to
buy goods or services
Central Place Theory
• Christaller tried to
determine the degree of
centrality of various places.
• He created a model to show
how central places in the
urban hierarchy are
spatially distributed.
• He assumed:
– No physical barriers
– Soil and surface of equal
quality
– Even distribution of
population
– Uniform transportation
system
Hexagonal Hinterlands
• Christaller’s urban model
showed that each central
place had a
complementary
hinterland.
• The hexagonal model
solves the overlap
problem that circles would
have.
• Nesting arrangementregion within a regioneach larger
complementary region is
centered on a higher order
urban place
Central Business District
• Downtown-the core of the
city with high-rise
skyscrapers, heavy traffic,
production, education,
services etc.
• The CBD is the urban
area of commercial &
industrial zones within a
ring of residential areas.
• Suburb-an outlying
residential area of the
urban region that is most
pronounced in the US
Bid Rent
• The price paid to rent or purchase urban land is a
reflection of its utility or usefulness.
• Utility is a product of accessibility to customers &
workers or for residents to jobs and amenities.
Modeling the North American City
• Concentric zone model (Ernest Burgess)
• Sector model (Homer Hoyt)
• Multiple Nuclei Model
(Chauncy Harris and Edward Ullman)
Classic Models of Urban Structure
• Ernest Burgess-1925
Concentric Zone Model
based on studies of
Chicago.
• CBD-financial, retail,
theater, museums etc.
• Transition to residential
with deterioration-some
light industry
• Blue collar labor housing
• Middle class residential
• Suburban ring
Functional
Zonation
The division of the
city into certain
regions (zones) for
certain purposes
(functions).
Cairo, Egypt
Central city (above)
Housing projects (right)
Classic Models of Urban Structure
• Homer Hoyt-1939
Sector Model based on
studies of 142 US cities.
• Pie-shaped wedges
created by Hoyt
compensated for the
drawbacks of the Ring
Model
• Low Rent areas & High
Rent areas could extend
to the outer edge
• Transportation and
industrial zones
accounted for the sectors
• Chauncy Harris & Edward Ullman Multiple Nuclei
Sector Model 1945 showed that CBD is not the sole force
in creating land-use patterns.
• They said that Concentric Rings & Pie-shaped models had
drawbacks as CBDs were losing dominance
• Subsidiary and competing CBDs developed (Edge Cities)
• Suburbanization accelerated the change with shopping malls
and mass transit
Why Do Inner Cities Still Attract People?
Recreational facilities
Orchestras, theaters and venues for popular music
concerts
Museums and art galleries
Sport teams and sporting arenas
Banks and high finance institutions
Universities and research facilities
Specialized research hospitals and medical
specialists
Shopping and specialized stores
Making Cities in the Global Core
• Redlining – financial institutions refusing to
lend money in certain neighborhoods.
• Blockbusting – realtors purposefully sell a
home at a low price to an African American
and then solicit white residents to sell their
homes at low prices, to generate “white
flight.”
Problems in Urban America
200 years ago only 5% of world was urbanized
Today about 50% is urban
Germany, Spain & Belgium are over 90% urban
World wide urban problems are:
pollution
poor sanitation
drugs and crime
congestion and noise
substandard housing & slums
Problems in Urban America
• With urban sprawl and
expanding suburbs-inner
city shrinks
• CBD is often reduced to
serving just the inner metro
area
• As basic sector jobs leavelarge cities have shifted to
service industries
• Loss of tax base as
businesses, industries and
services leave
• Urban decay results
Problems in Urban America
• New York City a good
example:
– 3 million people plus uncounted
illegals crowd into 75 to 100
year old apartment buildings
– Many buildings are worn out,
rat & roach infested with high
crime rates, vandalism and
cases of spouse & child abuse
• Yet despite the problems there
is a sense of community that
may be lost if the
neighborhood is torn down
• Deglomeration-as globalization and improved
communication and transportation have developed-many
businesses leave the high costs of downtown since it is no
longer an advantage to cluster with other similar
businesses-the results are rustbelt cities with urban decay,
loss of tax revenue and abandoned property
Making Cities in the Global Core
• Gentrification – individuals buy up and
rehabilitate houses, raising the housing value
in the neighborhood and changing the
neighborhood.
• Commercialization – city governments
transform a central city to attract residents and
tourists. The newly commercialized
downtowns often are a stark contrast to the rest
of the central city.