Delta Air Lines, Inc. is a large airline from the United States. They are headquartered in Atlanta, Georgia. Their largest hub is also in Atlanta. Delta's first flight was in 1929.[1] In 1972, Delta merged with Northeast Airlines.[2] In 1987, Delta merged with Western Airlines.[3] In 2009, they merged with Northwest Airlines. Until 2013, Delta was the world's largest airline.[4] As of February 2024, the airline goes to 325 cities and has 978 planes.[5] In 2017, they retired their largest aircraft, the Boeing 747, and replaced it with other planes such as the Airbus A350.