Spatial distribution of population and hierarchical system of cities (Case Study: Iran 1956-2011)

Urban population in the period of about fifty-five years from the first census in 1956 to census 2014 become more than 8 times and the rate of urbanization has increased to more than 2 times. The highest annual growth rate of urban population occurred between two censuses in 1976 and 1986. In seven censuses the classification of population in cities shows small towns with populations of less than 25 thousand people increase in terms of numbers but in terms of contribution to the urban population of the country have experi-enced a significant decline. In contrast, the share of the population of large towns and me-tropolis has increased. Metropolitan Tehran, as center of population attraction acts in this periods and the other major cities in terms of population, were far away. Index of urban priorities has always been more than one although many provinces had differences that urbanization indicators show the them more precisely. Findings from this study indicate that distribution of urban areas in the country and the province is more balanced, but the urban population is more concentrated.