Chattanooga is a city in and the county seat of Hamilton County, Tennessee, along the Tennessee River bordering Georgia. With an estimated population of 182,799 in 2019, it is the fourth-largest city in Tennessee and one of the two principal cities of East Tennessee, along with Knoxville. The city anchors the Chattanooga metropolitan area, the fourth largest metropolitan statistical area in Tennessee, 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. Chattanooga lies 118 miles (190 km) northwest of Atlanta, Georgia, 112 miles (180 km) southwest of Knoxville, Tennessee, 134 miles (216 km) southeast of Nashville, Tennessee, 102 miles (164 km) east-northeast of Huntsville, Alabama, and 147 miles (237 km) northeast of Birmingham, Alabama.
Chattanooga was a crucial city during the American Civil War, due to the multiple railroads in the city. After the war, the railroads allowed for the city to grow into one of the largest heavy industrial hubs in the Southeastern United States. Today, major industry that drives the economy includes automotive, advanced manufacturing, food and beverage production, healthcare, insurance, tourism, and back office and corporate headquarters.
The city, with a downtown elevation of about 680 feet (210 m), is at the transition between the ridge-and-valley portion of the Appalachian Mountains and the Cumberland Plateau. Its official nickname is "Scenic City", alluding to the surrounding by mountains and ridges. Unofficial nicknames include "River City", "Chatt", "Nooga", "Chattown", and "Gig City", the latter a reference to Chattanooga's claims that it has the fastest internet service in the Western Hemisphere.
Chattanooga is internationally known for the 1941 song "Chattanooga Choo Choo" by Glenn Miller and his orchestra.