Some of the cities, towns, and places in Sullivan County are Arcadia, Bloomingdale, Blountville, Bluff City, Boring, Bristol, Buffalo, Carter County, Cedar Grove (east), Cedar Grove (west), Colonial Heights, Fordtown, Holston Valley, Johnson City, Kingsport, Lynn Garden, Morrison City, Orebank, Piney Flats, Spurgeon, Sullivan Gardens, Walnut Hill, Washington County
Sullivan County is a county located in the U.S. state of Tennessee on its northeast border. As of the 2020 census, the population was 158,163. Its county seat is Blountville.Sullivan County is part of the Kingsport–Bristol TN-VA Metropolitan Statistical Area, which is a component of the Kingsport–Johnson City–Bristol, TN-VA Combined Statistical Area, commonly known as the "Tri-Cities" region.
Sullivan is Tennessee's second-oldest county; it was established in 1779 when the area was still part of North Carolina. From 1784 to 1788, it was part of the extra-legal State of Franklin.