www.chattanooga.gov Chattanooga is the fourth-largest city in the US state of Tennessee, with a population of 167,674 as of the 2010 census. It is the seat of Hamilton County. Located in southeastern Tennessee on Chickamauga Lake and Nickajack Lake, which are both part of the Tennessee River, Chattanooga lies approximately 120 miles (190 km) to the northwest of Atlanta, Georgia, 120 miles (190 km) to the southwest of Knoxville, about 135 miles (217 km) to the southeast of Nashville, and about 148 miles (238 km) to the northeast of Birmingham, Alabama. Chattanooga abuts the Georgia border, and the region is at the junction of three major interstate highways: I-24, I-75, and I-59. The city, which has a downtown elevation of approximately 680 feet (210 m), lies at the transition between the ridge-and-valley portion of the Appalachian Mountains and the Cumberland Plateau. The city is therefore surrounded by various mountains and ridges. The official nickname for Chattanooga is the Scenic City. Chattanooga is ranked 8th out of America's 100 largest metro areas for the best "Bang For Your Buck" city, according to Forbes magazine. The study measured overall affordability, housing rates, and more. Since 1990, Chattanooga has been recognized as a Tree City USA community.