Southwest Airlines to add new Hawaii destination: Hilo

Southwest Airlines is adding another destination in Hawaii but has not revealed the timing or flight details.

The airline, which began flights to Hawaii in March, plans to offer interisland flights to Hilo International Airport, on the island of Hawaii or "Big Island." Flights from the mainland to Hilo will not be offered. Travelers will have to connect in Honolulu.

Hilo is on the east side of the island. Most visitors to the island of Hawaii fly into Kona International Airport on the west side. The Hilo airport is the closest airport to Hawaii Volcanoes National Park, a popular tourist attraction. The park was temporarily closed a year ago because of a major volcanic eruption, and some parts remain closed.

Southwest announced the Hilo flights as it launched its first interisland flights to Kona on Sunday. The airline offers flights between Honolulu and Kona. Passengers from the mainland U.S. can book tickets to Kona with a stop in Honolulu.

Hawaiian Airlines and other carriers already offer service to Kona and Hilo.

Southwest has started slow in Hawaii. The airline only offers a handful of daily flights from Oakland and San Jose, California, to Honolulu and Maui.

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The airline previously announced plans to offer flights from two other California cities, San Diego and Sacramento, to Hawaii, but those flights have not begun and the airline is mum on when they will debut.

Southwest has also said it plans to fly to Kauai but has not revealed a timetable.

The airline's next schedule extension, which will open reservations into early January, is scheduled for June 20. The airline, which opens it schedule in increments instead of nearly a year in advance like most carriers, is currently accepting reservations through early November.

This article originally appeared on USA TODAY: Southwest Airlines to add new Hawaii destination: Hilo