The 1979 census showed that 51 percent of the population was urban, and this percentage remained unchanged through 1986. Rural population density in the mid-1980s was highest in the wellwatered regions of the north and the west and lowest in the arid and desert areas of the south and the east. The country as a whole averaged 1.36 people per square kilometer, with rural densities in 1986 ranging from 1.9 people per square kilometer in Bayan-Olgiy and Selenge aymags (see Glossary) to 0.22 people per square kilometer in Omnogovi Aymag (see fig. 1). The three largest cities--Ulaanbaatar, Darhan, and Erdenet--are in north-central Mongolia, on or near the main railroad line and the Selenge Moron or its major tributaries. Half the country's population lived in this core area, with its river valleys, productive upland pastures, coal and copper mines, and relatively well-developed transportation system. The remaining, much larger area--occupied by widely dispersed herders and by isolated administrative centers--was the economic and social periphery.

Data as of June 1989