Southwest Airlines, the nation's largest domestic carrier, begins flying outside of the borders of the U.S. on Tuesday, with flights to the Caribbean.
The expansion of service comes as part of Southwest's previously announced plan to take over the routes of its subsidiary, AirTran Airways.
Starting Tuesday, Southwest will take over AirTrans routes to the Bahamas, Aruba and Jamaica. The flights will originate from Atlanta, Baltimore, Orlando, Boston and Pittsburgh.
The airline said it will add flights to Cancun and Los Cabos, Mexico, starting Aug. 10, and to Mexico City and Punta Cana, Dominican Republic, on Nov. 2.
Details of Southwest's international service can be found at the airline's website. Passengers on the international routes can check two bags free of charge. Size and weight restrictions may differ from the rules for domestic flights.
Southwest executives have said they plan to eventually serve 96 destinations in six countries, including all the international stops now served by AirTran
To fly to international destinations, Southwest had to provide new training for crews and new equipment for its planes. For example, federal rules require planes that fly long distances over water to equip passenger seats with flotation devices. Many of Southwest's planes that fly domestic routes do not include such devices.