The Commonwealth of Kentucky is a state located in the east central United States of America. Kentucky is normally included in the group of Southern states, but it is sometimes included, geographically and culturally, in the Midwest. Kentucky is one of four U.S. states to be officially known as a commonwealth. Originally a part of Virginia, in 1792 it became the 15th state to join the Union. Kentucky is the 37th largest state in terms of land area, and ranks 26th in population.
Kentucky is known as the "Bluegrass State," a nickname based on the fact that bluegrass is present in many of the lawns and pastures throughout the state. It is a land with diverse environments and abundant resources, including the world's longest cave system, the most miles of navigable waterways and streams in the Lower 48 states, and the two largest man-made lakes east of the Mississippi River. It is also home to the highest per capita number of deer and turkey in the United States, and the nation's most productive coalfield. Kentucky is also known for thoroughbred horses, horse racing, bourbon distilleries, bluegrass music, automobile manufacturing (including the best selling car, truck, and SUV in the U.S. market), tobacco, and college basketball.
The origin of Kentucky's name (variously spelled Cane-tuck-ee, Cantucky, Kain-tuck-ee, and Kentuckee before its modern spelling was accepted) has never been definitively identified, though some theories have been debunked. For example, Kentucky's name does not come from the combination of "cane" and "turkey", nor does it mean "dark and bloody ground" in any known Indian language. The most likely etymology is that it comes from an Iroquoian word for "meadow" or "prairie" (c.f. Mohawk kenhta:ke, Seneca kehta'keh). Other possibilities also exist: the suggestion of early Kentucky pioneer George Rogers Clark that the name means "the river of blood", a Wyandot name meaning "land of tomorrow", a Shawnee term possibly referring to the head of a river, or an Algonquian word for a river bottom.
Kentucky borders states of both the Midwest and the Southeast. West Virginia lies to the east, Virginia to the southeast, Tennessee to the south, Missouri to the west, Illinois and Indiana to the northwest, and Ohio to the north and northeast. Kentucky's northern border is formed by the Ohio River; its western border by the Mississippi River.
Kentucky is the only U.S. state to have a non-contiguous part exist as an exclave surrounded by other states. Fulton County, in the far west corner of the state, includes a small part of land, Kentucky Bend, on the Mississippi River bordered by Missouri and accessible via Tennessee, created by the New Madrid Earthquake.
Kentucky can be divided into five primary regions: the Cumberland Plateau in the east, the north-central Bluegrass region, the south-central and western Pennyroyal Plateau, the Western Coal Fields and the far-west Jackson Purchase. The Bluegrass region is commonly divided into two regions, the Inner Bluegrass - the encircling 90 miles (145 km) around Lexington - and the Outer Bluegrass, the region that contains most of the Northern portion of the state, above the Knobs. Much of the outer Bluegrass is in the Eden Shale Hills area, made up of short, steep, and very narrow hills.