Abstract
This report is the fourth part of the series of studies on the size of city. In this report, we take up the third Block which is enclosed by main trank line of road, and public space (school, hospital, green, goverment office, factory, traffic, commarcial zone) Through the studies on the size of city (1), (2), (3), (4), finally we have classified each physical structure of cities Japan, and made model type of them basing on potenciality or strength of city.
