Downtown Atlanta is the first and largest of the three financial districts in the city of Atlanta. Downtown Atlanta is the location of many corporate or regional headquarters, city, county, state and federal government facilities, sporting facilities, and is the central tourist attraction of the city. The largest financial district also contains striking architecture that dates back to the 19th century while maintaining a modern look and feel. Finally, the area is also the location of the hub of MARTA rail lines and where the major Interstates meet each other with two of them forming the Downtown Connector.
As defined by the Central Atlanta Progress (CAP) organization, the area measures approximately four square miles, and had 23,300 residents as of 2006. This area is bound by North Avenue to the north, Boulevard to the east, Interstate 20 to the south, and Northside Drive to the west. This definition of Downtown Atlanta includes central areas like Five Points, the Hotel District and Fairlie-Poplar and outlying inner-city neighborhoods such as SoNo, and Castleberry Hill.
The Atlanta Downtown Improvement District (ADID) organization, though, defines a much smaller downtown area measuring just one and two tenths square miles. This area is roughly bound by North Avenue to the north, Piedmont Avenue and then Downtown Connector to the east, Martin Luther King Junior Drive, Courtland Street, and Edgewood Avenue to the south, and the railroad tracks to the west. This area only includes the core central business district neighborhoods of Fairlie-Poplar, Five Points, the Hotel District, Centennial Hills, and as of May 2007, the Railroad District.