. . . consider now the character of settlements within the region: what balance of villages, towns, and cities is in keeping with the independence of the region—Independent Regions?
Problem:
If the population of a region is weighted too far toward small villages, modern civilization can never emerge; but if the population is weighted too far toward big cities, the earth will go to ruin because the population isn't where it needs to be, to take care of it.
Background & Research: Not Included on the site—Go read the book!
Solution:
Encourage a birth and death process for towns within the region, which gradually has these effects: 1. The population is evenly distributed in terms of different sizes—for example, one town with 1,000,000 people, 10 towns with 100,000 people each, 100 towns with 10,000 people each, and 1,000 towns with 100 people each. 2. These towns are distributed in space in such a way that within each size category the towns are homogeneously distributed all across the region. This process can be implemented by regional zoning policies, land grants, and incentives which encourage industries to locate according to the dictates of the distribution.
Usage:
As the distribution evolves, protect the prime agricultural land farming—Agricultural Valleys; protect the smaller outlying towns, by establishing belts of countryside around them and by decentralizing industry, so that the towns are economically stable—Country Towns. In the larger more central urban areas work toward land policies which maintain open belts of countryside between the belts of city—City Country Fingers . . .
pg. 16