Sullivan County sits at the center of the Tri-Cities region of northeast Tennessee, with a scenic skyline, miles of mountains in the Cherokee National Forest, and three large lakes built by the Tennessee Valley Authority. Well-known county crossroads include Colonial Heights and Bloomingdale, while famous local landmarks include Warriors Path State Park; the stalagmites of the Appalachian Caverns and Bristol Caverns; the "World's Fastest Half-Mile Track" at Bristol Motor Speedway; the "Birthplace of Country Music" at Bristol; and the Grand Guitar, the world's only guitar-shaped museum. Piney Flats is the home of Rocky Mount, once the capitol building of "the Territory of the United States South of the River Ohio." Bluff City boasts railroad history and Civil War stories along the South Fork of the Holston River. Kingsport lays claim to Netherland Inn, Bays Mountain Park, and the Long Island of the Holston, a sacred place for the Cherokees. The courthouse town of Blountville holds the distinction of being the only county seat in Tennessee that is not incorporated.