Clarksville is the county seat of Montgomery County, Tennessee, United States. It is the fifth-largest city in the state behind Nashville, Memphis, Knoxville, and Chattanooga. The city had a population of 166,722 as of the 2020 United States census.It is the principal central city of the Clarksville, TN–KY metropolitan statistical area, which consists of Montgomery and Stewart counties in Tennessee, and Christian and Trigg counties in Kentucky. The city was founded in 1785 and incorporated in 1807, and named for General George Rogers Clark, frontier fighter and Revolutionary War hero, and brother of William Clark of the Lewis and Clark Expedition.Clarksville is the home of Austin Peay State University; The Leaf-Chronicle, the oldest newspaper in Tennessee; and neighbor to the Fort Campbell, United States Army post. Site of the 101st Airborne Division (Air Assault), Fort Campbell is located about 10 miles (16 km) from downtown Clarksville, and spans the Tennessee-Kentucky state line.

Hopkinsville is a home rule-class city in and the county seat of Christian County, Kentucky, United States. The population at the 2010 census was 31,577.

Lake Barkley, a 58,000-acre (230 km2) reservoir in Livingston County, Lyon County and Trigg County in Kentucky and extending into Stewart County and Houston County in Tennessee, was impounded by the U.S. Army Corps of Engineers in 1966 upon the completion of Barkley Dam. Both the lake and the dam are named for Vice President Alben Barkley, a Kentucky native.The dam impounds the Cumberland River near Grand Rivers, Kentucky, approximately 38 miles (61 km) upstream from where the Cumberland empties into the Ohio River. One mile (1.6 km) above the dam is a canal connecting Lake Barkley with Kentucky Lake, forming one of the greatest freshwater recreational complexes in the country. The lakes run parallel courses for more than 50 miles (80 km), with the Land Between The Lakes National Recreation Area located between them. Lake Barkley is 134 miles (216 km) long with a shoreline measuring 1,004 miles (1,616 km). The lake's level is maintained at different levels throughout the year for flood control purposes. Summer pool, 359 ft (109 m) above sea level, is normally reached by May 1. The water level begins dropping gradually on July 1, and winter pool (354 ft/107 m) is reached by December 1. The spring rise starts April 1. The lake's water surface area varies accordingly from 57,920 acres (234 km²) at summer pool to 45,210 acres (183 km²) at winter pool.

Greenville is a home rule-class city in Muhlenberg County, Kentucky, in the United States. It is the seat of its county. The population was 4,312 at the 2010 census.