Chattanooga is a city in and the county seat of Hamilton County, Tennessee, along the Tennessee River bordering Georgia. The city also extends into Marion County on its western end. With a population of 181,099 in 2020, it is Tennessee's fourth-largest city and one of the two principal cities of East Tennessee, along with Knoxville. The city anchors the Chattanooga metropolitan area, Tennessee's fourth-largest metropolitan statistical area, as well as a larger three-state area that includes Southeast Tennessee, Northwest Georgia, and Northeast Alabama. Served by multiple railroads and Interstate highways, Chattanooga is a transit hub. It is 118 miles northwest of Atlanta, Georgia, 112 miles southwest of Knoxville, Tennessee, 134 miles southeast of Nashville, Tennessee, 102 miles east-northeast of Huntsville, Alabama, and 147 miles northeast of Birmingham, Alabama.
Chattanooga was a crucial city during the American Civil War, due to the multiple railroads that converge there. After the war, the railroads allowed for the city to grow into one of the Southeastern United States' largest heavy industrial hubs.