A minute observation shows that in each state there are variations in distribution of population and more than one category of population density is found. The geographical or spatial distribution becomes more clear by making an analysis of district level pattern.
The great unevenness in distribution is mainly because of the diverse physical conditions as well as the variations in distribution of natural resources and stages of economic development. It varies from 2 persons per square kilometre in Lahul and Spiti district of Himachal Pradesh to 29,395 persons per square kilometre in National Capital Territory of Delhi.
The top twenty districts in the country are either fully urban or highly urbanized. It includes all the nine districts of Delhi; Kolkata, Hawrah, North Twenty-Four Pargana in West Bengal; Mumbai and Mumbai (suburban) in Maharashtra; Mahe and Pondicherry in Union Territory of Pondicherry, Chennai; Bangalore; Hyderabad and Union Territory of Chandigarh.
The density is generally high over two marked continuous stretches of land. They are (a) large parts of Northern plains from Punjab to West Bengal and (b) Coastal plains from Orissa coast in the east to Konkan coast in the west.
A belt of moderately high densities extend over the entire Maharashtra, plains of Gujarat, Telangana, parts of Tamil Nadu, southern Karnataka and the Chhotanagpur region of Jharkhand. The areas of low density are generally found over the hilly forested and snow bound areas of the country, mainly situated in the Himalayan region, desert areas of Rajasthan specifically Jaisalmer districts and large expanse of uninhabited marshy lands of Kachchh districts of Gujarat.