Memphis is a city in the southwestern corner of the U.S. state of Tennessee, and the county seat of Shelby County. The city is located on the 4th Chickasaw Bluff, south of the confluence of the Wolf and Mississippi rivers. Memphis had a population of 646,889 at the 2010 census making it the largest city in the state of Tennessee, the third largest in the Southeastern United States, and the 20th largest in the United States. The greater Memphis metropolitan area, including adjacent counties in Mississippi and Arkansas, had a 2010 population of 1,316,100. This makes Memphis the second largest metropolitan area in Tennessee, surpassed only by metropolitan Nashville, which has overtaken Memphis in recent years. Memphis is the youngest of Tennessee's major cities. A resident of Memphis is referred to as a Memphian, and the Memphis region is known, particularly to media outlets, as "Memphis & The Mid-South".
Downtown Memphis rises from a bluff along the Mississippi River, and the city sprawls outward over southwest Tennessee and into northern Mississippi and eastern Arkansas. Several large parks are scattered through the city, notably Overton Park in Midtown and the 4,500 acres (18 km2) Shelby Farms. The city is a national transportation hub and Mississippi River crossing for Interstate 40, (east-west), Interstate 55 (north-south), barge traffic, Memphis International Airport (FedEx's "SuperHub" facility) and numerous freight railroads that serve the city.
The city's central location has led to much of its business development. Located on the Mississippi River and intersected by five major freight railroads and two Interstate highways, I-40 and I-55, Memphis is ideally located for commerce in the transportation and shipping industry. A third interstate, I-69, is under construction, and a fourth, I-22, has recently been designated from the former High Priority Corridor X. River barges are unloaded onto trucks and trains. The city is home to Memphis International Airport, the world's second busiest cargo airport (following Hong Kong), which serves as the primary hub for FedEx Express shipping and was a secondary hub for Delta Air Lines after it merged with Northwest Airlines in 2008. Memphis is the home of three Fortune 500 companies: FedEx, AutoZone, and International Paper. Other major corporations based in Memphis include Allenberg Cotton, American Residential Services (also known as ARS/Rescue Rooter), Baker, Donelson, Bearman, Caldwell & Berkowitz, Cargill Cotton, First Horizon National Corporation, Evergreen Packaging, Fred's, GTx, Guardsmark, Lenny's Sub Shop, Perkins Restaurant and Bakery, Pinnacle Airlines, ServiceMaster, Thomas & Betts, True Temper Sports, Varsity Brands, and Verso Paper. Corporations with major operations based in Memphis include Carrier, Merck & Co., Medtronic, Sharp Manufacturing, Smith & Nephew, and Technicolor Home Entertainment Services.