Paducah is a home rule-class city in and the county seat of McCracken County, Kentucky, United States. The largest city in the Jackson Purchase region, it is located at the confluence of the Tennessee and the Ohio rivers, halfway between St. Louis, Missouri, to the northwest and Nashville, Tennessee, to the southeast. The population was 24,864 in 2015, down from 25,024 during the 2010 U.S. Census. Twenty blocks of the city's downtown have been designated as a historic district and listed on the National Register of Historic Places.Paducah is the hub of its micropolitan area, which includes McCracken, Ballard and Livingston counties in Kentucky and Massac County in Illinois.