(Charles Dharapak/AP)

Southwest Airlines announced today that it was adding service between Hartsfield-Jackson Atlanta International Airport and five cities. The additional service includes four daily nonstop round trips between Atlanta and Baltimore-Washington International Marshall Airport.

Other routes added include Atlanta service to Austin, Denver, Houston Hobby and Chicago Midway airports. Trips are available for booking today with service beginning Feb. 12.

Southwest said rates begin at $79 each way between Atlanta and BWI.

The news follows Southwest’s recent acquisition of AirTran, which officials had said would lead to the expansion of Southwest service. With the merger Southwest became the Washington region’s dominant carrier, controlling about 32 percent of the area’s air travel.

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