1. Urban Models & Theories: How are Cities Organized & How do they Function?

2. A. Urban Morphology The layout of a city, its physical
form & structure
Berlin, Germany
With wall (above)
And without wall (right)

3. B. Functional Zonation Division of city into regions (zones) for
certain purposes
(functions)
Cairo, Egypt
Central city (above)
Housing projects (right)

4. C. The Changing City & John Borchert
4 epochs in evolution of Amer. metropolis based on impact of transportation & communication:
Sail-Wagon Epoch ( ) – associated w/ low technology
Iron Horse Epoch ( ) – steam-powered locomotive & spreading rails
Steel-Rail Epoch ( ) – full impact of Ind. Rev. (steel), hinterlands expand

5. C. The Changing City & John Borchert
Auto-Air-Amenity Epoch ( ) – gas-powered internal combustion engine
High Technology Epoch? (1970-?) – service & information industries
(NOT part of Borchert’s model)

6. D. Modeling the North American City
All cities have the following:
Central business district (CBD)
Central City (CBD + older housing zones)
Suburb (outlying, functionally uniform zone outside of central city)

7. E. Concentric Zone Model
Created by Ernest Burgess (1920s Chicago)
Divides city into 5 concentric zones, defined by function
Newest settlers use older housing near city center (migrants to industrial jobs)
Previous groups move outward to higher-income areas as they assimilate
Concentric pattern arises as land uses compete and are sorted according to ability to pay for land
As one moves toward central city, land becomes scarcer but accessibility improves, rent therefore increases, and land uses that cannot exact sufficient rent are sorted out
Similar activities likely to be found at similar distances from central business district (CBD)

8. 5 Rings of Model
1) CBD – at center of model
2) Zone of transition (residential deterioration & light industry)
3) Zone of independent worker’s homes (blue-collar workers)
4) Zone of better residences (Middle-class)
5) Commuters Zone (Suburbs)

10. F. Sector Model
Created by Homer Hoyt (1939); criticized Burgess Model as too simple & inaccurate
Focuses on residential patterns
Assumes land use is conditioned by transportation routes radiating outward from city center
High-income areas along fashionable boulevards, waterfronts, or high ground
Industry along river or rails
Low-income near industry
Middle-income btwn. low and high sectors

11. City grows outward from center, so a low-rent
area could extend from CBD to city’s outer edge
Same is true w/ high-rent, transportation, and industry

12. G. Multiple Nuclei Model
Created by Harris & Ullman (1945)
Seen in post WWII – early suburbanization
Downtown CBD not only core of business land use
Other nuclei develop - special retail districts, office parks, light manufacturing in city
Metro areas develop “suburban downtowns” (called “edge cities”)

14. Transportation and Urban Growth
DISCUSSION:
* Do you recognize aspects of the layout of your town or city that are remnants of past transportation eras? *

15. H. Edge Cities
Suburban nodes: high-rise offices, shopping, entertainment, hotels - designed for auto travel
Located along freeways/beltways
3 distinct varieties of edge city phenomenon:
Boomburgs: the most common type, having developed incrementally around a shopping mall or highway interchange
Greenfields: having been master-planned as new towns, generally on suburban fringe
Uptowns: historic activity centers built over older city or town (sometimes a satellite city)
Ex: Tyson’s Corner

16. Tyson’s Corner

17. Tysons Corner is poised to become North America's only example of a former sprawling edge city becoming a fully-fledged downtown in its own right

18. I. Galactic City or Peripheral Model (AKA Edge City Model)

19. Philadelphia's Edge Cities
DISCUSSION:
* What are the elements required for a suburban area to be categorized as an "edge city"? *