Synopsis Jharia coalfield in Dhanbad district of Jharkhand state occupies an important place not only in the coal mining history of the country but also the globe due to typical features of the coal deposits. In the country this coalfield is the only source of prime coking coal and the coalfield has been serving the nation for about 110 years. Coal mining in the coalfield was stated in 1893-94. The coalfield belonging to Gondwana period has a unique feature that in a strata thickness of about 600 m there are over 40 workable coal horizons making the percentage of coal about 12. The total proved reserves of the coalfield are about 11.4 billion tonne out of which about 20-25% have been exploited so far and the remaining reserves are still available. The last 100 years of mining has made gross changes in the demography and land use of the coalfield as a result of which the coalfield today is having about one-third of the land area under settlements / colonies / villages, which is probably the highest density anywhere in the world. Originally a tribal area has now become a cosmopolitan conglomerate with people from all the parts of the country residing the coalfield and the surrounding areas.