Paducah is a city in the Upland South, and the county seat of McCracken County, Kentucky, United States. The most populous city in the Jackson Purchase region, it is located in the Southeastern United States at the confluence of the Tennessee and the Ohio rivers, halfway between St. Louis, Missouri, to the northwest and Nashville, Tennessee, to the southeast. As of the 2020 census, the population was 27,137, up from 25,024 in 2010. Twenty blocks of the city's downtown have been designated as a historic district and listed on the National Register of Historic Places.