Middlesborough, also spelled Middlesboro, is a city in Bell County, Kentucky, United States. The population was 12,251 at the 2000 census. However the micropolitan cluster that consist of the entire population not included in the 2000 census, including suburbs Ambleside, Vista Venado and off sites of the Belt line and yes town increases Middlesboro's population to 18,792. The entire Micropolitan area has a population of 68,890 which includes Bell and Whitley counties. It is the principal city of the Middlesborough, KY Micropolitan Statistical Area. Middlesborough apartments for rent comparison page shows most up to date rent information on Middlesborough apartments and houses. Rent information is obtained from multiple rental sources but we cannot guarantee their accuracy.