Nicholas County is a county located in the U.S. state of Kentucky. As of the 2020 census, the population was 7,537. Its county seat is Carlisle, which is also the only incorporated community in the county. Founded in 1799, the county is named for Col. George Nicholas, the "Father of the Kentucky Constitution."

Robertson County is a county located in the U.S. Commonwealth of Kentucky. As of the 2020 census, the population was 2,193. Its county seat is Mount Olivet. The county is named for George Robertson, a Kentucky Congressman from 1817 to 1821. It is Kentucky's smallest county by both total area and by population.