The Nehamiah, a 57-foot wooden ketch, has been around the world two and a half times.

But last year, the vessel may have made one of its most unusual ventures — off Vallejo’s coastline to engage in a ship-to-shore cannon battle with pirates.

The vessel will make its second appearance this year at the Northern California Pirate Festival on Saturday and Sunday, participating again with the Brotherhood of Oceanic Mercenaries (BOOM) in one of the highlights of the event.

“We didn’t start out last year expecting to be asked,” said Joni Phillips, wife of the Nehamiah’s captain, Rod Phillips, who keep the ketch in Marina Bay in Richmond.

The couple was surprised to get an email last year from the festival organizers, who were seeking a successor to the Aldebaran, a red-sailed schooner that was severely damaged when it went aground after a 2013 Independence Day sail.

Hayden Brown, the Aldebaran’s builder and owner, tried unsuccessfully to get his vessel restored with the help of volunteers and an Internet crowdfunding effort.

That sent pirate festival organizers on a search for a sailboat that could accommodate guns simulating cannonfire the way the Aldebaran’s line-throwing Lyle guns could. After all, the ship-to-shore cannon battle has become a staple of the event — in fact it’s one of the most-anticipated features of the festival.

Normally, the Nehamiah is the vessel of Crosscurrent Voyages, a nonprofit organization, and has other roles to perform, such as a charter vessel for parties, memorials and family gatherings.

The ketch was built of Port Orford cedar in 1971. Its crafters then took it around the world.

Its next owners did the same, then used it to cruise the South Seas.

The Phillipses bought the ship 20 years ago, sailing it to Catalina and the Channel Islands before bringing it to the Bay Area.

Like all wooden vessels, the Nehamiah requires more upkeep than ships made of modern materials, Phillips said. But the cooler waters of Northern California mean the ketch needs less maintenance than if it belonged to pirates sailing in the Caribbean.

Like many larger sailboats and tall ships, the Nehamiah also is a classroom that is used to give youth a practical, hands-on sailing experience, such as tying and untying the vessel, handling sails and lines, learning about knots, rowing, anchoring, navigation, chart reading, record keeping, operating a marine radio and general sailboat maintenance.

“We’ve had church and school groups, an exploratory school from the Sierras, and from the outskirts of California,” Phillips said. The ketch also has been host to Boy Scouts, including members from Russia, and “we’ve also had the Pasadena Boys Choir along.”

Youths’ adventure is coupled with science education and character development.

The charter cruises, whether for private or public cruises on Bay Area waters, help support the youth opportunities, Phillips said. It can accommodate 29 passengers.

But when the Northern California Pirate Festival called, the Phillipses answered.

“The email came out of the blue,” Joni Phillips said. “We enlisted our regular crew. They were enthusiastic.”

They sailed their ship to Vallejo the night before last year’s festival, giving a pre-show sunset cruise to friends, including a Catholic priest.

“The next morning, we did the first day. That Saturday, we had a nice wind. All the sails were up. I was not on board — I was taking pictures!” Phillips said. Her husband, who also is a captain with the Red and White Fleet of San Francisco Bay Boat Tours and Sightseeing, was the ship’s leader during the battle sails.

The Phillipses’ organization didn’t have pirate costumes, but they outfitted the crew in period white puffy shirts so they’d look the part. Also on board were BOOM members in their elaborate attire.

By the second battle sail, Phillips said, “We knew what to expect.”

The couple had not been to the festival before, and had not realized that one reason it takes place at the Vallejo Waterfront Park is because Vallejo allows organizers to have the cannon fights. “I didn’t know that until I was there. Then it makes a lot of sense,” Phillips said.

Unlike the Aldebaran, the Nehamiah can be sailed with just two people, a captain and a deck hand, according to U.S. Coast Guard requirements. “A ketch is easier to handle than a schooner,” Phillips said. But viewed from the coastline, the two vessels have a similar appearance.

Phillips said she prefers a crew of three or more aboard the couple’s vessel, and for the festival the Nehamiah probably will have eight to 10 crew members, not counting the BOOM cannoneers.

“I’ve looked ahead at the weather. It will be about 77 degrees — I like 77 degrees.” Winds will be about 15 knots, a good strength for the ketch.

She’s looking forward to the event. “We love to see the costumes,” she said. “This isn’t something we see every day.”

Those interested in sailing aboard the Nehamiah on its public and private charters, through its youth program or as volunteers may visit the Phillipses’ website, www.sailingacross.com/.