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."

Carlisle is a home rule-class city in Nicholas County, Kentucky, United States. The population was 2,010 at the 2010 census. It is the county seat of Nicholas County. It is located at the junction of Kentucky Route 32 and Kentucky Route 36, about halfway between Lexington and Maysville.