The Commonwealth of Kentucky, also known as the "Bluegrass State", is one of four U.S. states constituted as a commonwealth along with Virginia, Pennsylvania and Massachusetts.

Originally a part of Virginia, in 1792 Kentucky split from it and became the 15th state to join the Union. Kentucky is the 37th most extensive and the 26th most populous of the 50 United States.

Kentucky is nicknamed for bluegrass, a species of grass found in many of its pastures. One of the major regions in Kentucky is the Bluegrass Region in central Kentucky, which houses two of its major cities, Louisville and Lexington. It is a land with diverse environments and abundant resources, including the world's longest cave system, Mammoth Cave National Park, one of the greatest lengths of navigable waterways and streams in the contiguous United States, and the two largest man-made lakes east of the Mississippi River.