To study distribution of cities, geographers look at 3 key traits: population, trade area, and distance.
Trade area is the adjacent region within which the city is dominant. Example is Green Country around Tulsa, OK.
These 3 features create a sort of hiearchy between cities. For example, San Francisco/San Jose would be the dominant city here since they have large trade areas and populations.
Rank size rule states that population of city should be inversely proportional to place in hiearchy, unless there is one immensely influential city in a country, like Mexico or France.[
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Central Place Theory
Walter Christaller laid the foundation for CPT when explaining where cities, towns, and villages are likely to be located.
Assumptions for ideal region:
- Flat land
- Consistent soil fertility
- Evenly distributed population/purchasing power
- Thorough transportation
- Accessible goods
Central place should be nested -> easy to provide to auxiliary locations. Therefore, centers of cities should be centers of goods so they can maintain monopoly of certain goods in trade area.
Hexagonal Hinterlands
Hexagonal regions are best model of cities and trade areas and held true in some places very well.
Examples of it working:
- North China Plain and Sichuan Basin are flat ground.
- G. William Skinner said areas fit model
- US Midwest had similar economic forces
Central Places Today
Internet has changed the world -> CPT might not hold true. However, it still explains many phenomena.
Sunbelt Phenomenom
- Millions of Americans move from N/NE states to S/SW states because of governmental policies favoring cities in “Sunbelt” with federal spending
- Demonstrates how big cities will increase technological goods in accordance with CPT to maintain power/go up in hiearchy