Why are cities located in certain areas? Development of Cities Why are cities located in certain areas?
Site and Situation Site Situation * absolute location of a city * a city’s static location, often chosen for trade, defense, or religion. Situation * relative location of a city * a city’s place in the region and the world around it.
Where Are Cities Located, and Why? Urban geographers discovered that every city and town has a trade area, an adjacent region within which its influence is dominant. Three key components arise frequently in urban geography: population, trade area, and distance. Concept Caching: Mount Vesuvius
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Central Place Theory Walter Christaller developed a model to predict how and where central places in the urban hierarchy (hamlets, villages, towns, and cities) would be functionally and spatially distributed. Assumed: 1. surface is flat with no physical barriers 2. soil fertility is the same everywhere 3. population and purchasing power are evenly distributed 4. region has uniform transportation network 5. from any given place, a good or service could be sold in all directions out to a certain distance
The market areas of settlements (hinterlands) overlap one another at different scales. Large settlements have larger market areas but they are few in number. Consumers are willing to travel longer distances to access services. Small settlements have smaller, more numerous market areas which are closer to consumers.
Hexagonal Hinterlands C = city T = town V = village H = hamlet
Why hexagons are used in theory to delineate market areas. Figure: 12-05 Title: Why hexagons are used in theory to delineate market areas. Caption: (a) Circles are equidistant from center to edge, but they overlap or leave gaps. (b) Squares nest together without gaps, but their sides are not equidistant from the center. (c) Geographers use hexagons to depict the market area of a good or service, because hexagons offer a compromise between the geometric properties of circles and squares. Circles are equidistant from center to edge, but they overlap or leave gaps. Squares nest together without gaps, but their sides are not equidistant from the center. Geographers use hexagons to depict the market area of a good or service, because hexagons offer a compromise between the geometric properties of circles and squares.
Best location for a pizza delivery service Figure: 12-06 Title: Best location for a pizza delivery service. Caption: (top) Best location for a pizza-delivery service in a linear settlement with seven potential customers, families A through G. The optimal location for the shop is between 5th and 6th streets, the median location. The delivery van would travel four blocks to deliver a pizza to Family A (between 1st and 2nd streets), three blocks to Family B (between 2nd and 3rd), two blocks to Family C (between 3rd and 4th), zero blocks to Family D (between 5th and 6th), two to Family E (between 7th and 8th), ten to Family F (between 15th and 16th), and 11 to Family G (between 16th and 17th). The van would have to travel a total of 32 blocks to deliver a pizza to each of the seven customers, three located to the west and three to the east. (bottom) Best location for a pizza-delivery service in a linear settlement with 99 families. Numbers in each apartment building represent families at each location. The median location is the middle observation among these 99 families, the place where 49 families live to the west and 49 families live to the east. Geo Pizza should locate between 7th and 8th streets.
Convenience stores Figure: 12-08 Title: Convenience stores. Caption: Market area, range, and threshold for Kroger supermarkets (left) and United Dairy Farmers (UDF) convenience stores (right) in the Dayton, Ohio, metropolitan area. Fewer stores are in the southwest and northeast, which are predominantly industrial areas, and in the west, which contains lower-income residents. Compared to Kroger supermarkets, UDF stores are more numerous and have smaller market areas, ranges, and thresholds. Market area, range, and threshold for Kroger supermarkets (left) and United Dairy Farmers (UDF) convenience stores (right) in the Dayton, Ohio, metropolitan area. Fewer stores are in the southwest and northeast, which are predominantly industrial areas, and in the west, which contains lower-income residents. Compared to Kroger supermarkets, UDF stores are more numerous and have smaller market areas, ranges, and thresholds.
Rank-Size Rule: in a model urban hierarchy, the population of the city or town will be inversely proportional to its rank in the hierarchy. For example: largest city = 12 million 2nd largest = 6 million 3rd largest = 4 million 4th largest = 3 million Example: Most US Cities
Primate City The leading city of a country. The city is disproportionately larger than the rest of the cities in the country. For example: London, UK Mexico City, Mexico Paris, France - the rank-size rule does not work for a country with a primate city
http://flowingdata.com/2010/03/10/what-burger-chain-reigns-supreme/