The Tennessee Valley is the drainage basin of the Tennessee River and is largely within the U.S. state of Tennessee. It stretches from southwest Kentucky to north Alabama and from northeast Mississippi to the mountains of Virginia and North Carolina. The border of the valley is known as the Tennessee Valley Divide. The Tennessee Valley contributes greatly to the formation of Tennessee's three legally recognized sectors.

The Tennessee River is the largest tributary of the Ohio River. It is approximately 652 miles (1,049 km) long and is located in the southeastern United States in the Tennessee Valley. The river was once popularly known as the Cherokee River, among other names, as the Cherokee people had their homelands along its banks, especially in what are now East Tennessee and northern Alabama. Additionally, its tributary, the Little Tennessee River, flows into it from Western North Carolina and northeastern Georgia, where the river also was bordered by numerous Cherokee towns. Its current name is derived from the Cherokee town, Tanasi, which was located on the Tennessee side of the Appalachian Mountains.