The Eastern Kentucky Coalfield is part of the Central Appalachian bituminous coalfield, including all or parts of 30 Kentucky counties and adjoining areas in Ohio, West Virginia, Virginia and Tennessee. It covers an area from the Allegheny Mountains in the east across the Cumberland Plateau to the Pottsville Escarpment in the west. The region is known for its coal mining; most family farms in the region have disappeared since the introduction of surface mining in the 1940s and 1950s.