Columbia is a home rule-class city just above Russell Creek in Adair County, Kentucky, United States. The population was 4,452 at the 2010 census. Columbia is the seat of its county.

Adair County is a county located in the U.S. state of Kentucky. As of the 2020 census, the population was 18,903. Its county seat and only municipality is Columbia. The county was founded in 1801 and named for John Adair, then Speaker of the House in Kentucky and later Governor of Kentucky. Adair County has some of the few surviving American Chestnut trees in the United States.