Hickman County is a county located in the U.S. state of Kentucky. As of the 2020 census, the population was 4,521, making it the third-least populous county in Kentucky. Its county seat is Clinton. The county was formed in 1821. It is the least densely populated county in the state and is a prohibition or dry county.

Fulton County is the westernmost county in the U.S. state of Kentucky, with the Mississippi River forming its western boundary. As of the 2020 census, the population was 6,515. Its county seat is Hickman and its largest city is Fulton. The county was formed in 1845 from Hickman County, Kentucky and named for Robert Fulton, the inventor of the steamboat.