The Ohio River, running along the state's northern border, separates Kentucky from Illinois, Indiana, and Ohio. West Virginia borders Kentucky to the northeast across the Big Sandy River, and Virginia borders Kentucky to the southeast. Tennessee borders Kentucky to the south, and Missouri adjoins the extreme western edge of the state across the Mississippi River. It includes some of the most diverse areas within the eastern United States. In the eastern part of the state lies the Eastern Coal Fields, a rugged, mountainous area covered with forests and dissected by streams.
Most level land is restricted to river valleys.
The western edge of the Eastern Coal Field encompasses most of the Daniel Boone National Forest. In the gently rolling central part of the state, the Bluegrass region lies to the north and the Mississippian Plateau to the south, separated by a chain of low steep hills called the Knobs. The Western Coal Field, bordered on the north and northwest by the Ohio River lies in the Illinois basin. The southwest corner of the state is a low, flat plain called the Jackson Purchase. The lowest elevation in the state is located in this region in Fulton County on the Mississippi River - 260 feet above sea level.