The capital and most populous city of the United States state of Georgia is Atlanta. It is also the 37th most populated city in the United States, with an estimated population of 506,811. The city is the cultural and economic hub of the Atlanta metropolitan region, which has a population of over six million people and is the country's ninth-largest metropolitan area. Atlanta is the county seat of Fulton County, Georgia's most populated county. A portion of the city extends into DeKalb County to the east. The city is nestled in the Appalachian Mountains' foothills and has the greatest elevation of any major city east of the Mississippi River.