Leslie County is located in the U.S. state of Kentucky. Its county seat and largest city is Hyden. As of the 2020 census, the population was 10,513. It was formed in 1878 from portions of Clay, Harlan, and Perry counties, and named for Preston Leslie, governor of Kentucky from 1871 to 1875.

Clay County is a county located in the U.S. state of Kentucky. As of the 2020 census, the county population was 20,345. Its county seat is Manchester. The county was formed in 1807 and named in honor of Green Clay (1757–1826). Clay was a member of the Virginia and Kentucky State legislatures, first cousin once removed of Henry Clay, U.S. Senator from Kentucky and Secretary of State in the 19th century.