Bristol is a city in Sullivan County, Tennessee, United States. The population was 26,702 at the 2010 census. It is the twin city of Bristol, Virginia, which lies directly across the state line between Tennessee and Virginia. The boundary between the two cities is also the state line, which runs along State Street in their common downtown district. Bristol is a principal city of the Kingsport-Bristol-Bristol, TN-VA Metropolitan Statistical Area, which is a component of the Johnson City-Kingsport-Bristol, TN-VA Combined Statistical Area - commonly known as the "Tri-Cities" region.