AVALON, Calif. (AP) — The mountaintop runway on Santa Catalina Island, a tourist destination off the Southern California coast, has reopened after five months of construction.

A World War II-era DC-3 touched down on the new runway at the Airport in the Sky to mark the occasion on Friday, the Orange County Register reported . It was followed by six CJ-6 Warbirds that flew in formation over the runway and two more war-era aircraft that made a high-speed, low-altitude fly-by.

About 100 U.S. Marines and Navy sailors began working on the island in December under an agreement between the military and the Catalina Island Conservancy to rebuild the deteriorating runway.

The project was paid for by $5 million donated to the nonprofit land trust. The military performed the work as part of a training exercise.

The conservancy had been patching the runway at a cost of about $250,000 a year until the state Department of Transportation's aeronautics division said it needed a long-term repair plan. The trust then partnered with the Defense Department's Innovative Readiness Training Program, which looks to match up the needs of communities with military training opportunities.

Military officials said the operation helped them consider the logistics of getting construction supplies and equipment on an island with little infrastructure. The Marines and sailors lived in tents near the airport and faced setbacks when winter storms loosened the soil and blew away a shower trailer.

"A lot of what you do is training for the worst-case scenario, but you never know what you're faced with," Marine Corps Lt. Col. James Bauch said. "You try to get people conditioned with as many different skill sets as you can."

The airport dates to 1941, when it was built by leveling two mountaintops and filling in the remaining canyon to create the 3,000-foot (914-meter) main runway, which sits at an elevation of about 1,600 feet (488 meters) about 10 miles (16 kilometers) from the city of Avalon.

One end of the runway has a huge drop-off. Using it has been likened to landing on an aircraft carrier.

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