Smith County is a county in the U.S. state of Tennessee. As of the 2020 census, the population was 19,904. Smith County is located in the region of the state known as Middle Tennessee. Its county seat is Carthage. The county was organized in 1799 and is named for Daniel Smith, a Revolutionary War veteran who made the first map of Tennessee and served as a United States senator.

The Nashville metropolitan area is a metropolitan statistical area in north-central Tennessee. Its principal city is Nashville, the capital of and largest city in Tennessee. With a population of over 2 million, it is the most populous metropolitan area in Tennessee. It is also the largest metropolitan area in Tennessee in terms of land area.