WILMINGTON, N.C. (WWAY, CBS NEWSPATH) — A couple strolling Kure Beach near Wilmington, North Carolina looking for seashells made a discovery that they definitely weren’t expecting.

“This will never happen in our lifetime again,” Patti Belanger said.

This started as a hunt for seashells.

“We were walking south from our house down to Fort Fisher. We look for seashells. Seashells and shark teeth,” Belanger said.

But Patti and Kerry Belanger’s daily walk on the beach was about to turn into a treasure hunt.

“I looked down into about 6 inches of water and I thought, ‘What is that?’” Belanger said. “So I said to Kerry, ‘What is that?’ and he says, ‘It’s a rock.’ But I said, ‘I don’t think that’s a rock.”

Kerry started digging.

“It literally looked like a big bullet,” Belanger said.

Patti says it was too heavy to carry, but she was not going to leave it behind.

“I wasn’t going to let it go,” Belanger said.

Kerry threw it over his shoulder and they took it home.

“We talked about it a lot. I thought, ‘We just don’t know if this is safe or not,” Belanger said.

So where did she turn? Facebook, of course.

“We put that out there and immediately the hits started coming,” Belanger said.

That’s when Patti says they decided to call the police.

“I was sitting in my chair reading a book, and I heard a voice behind me say, ‘Hi are you the lady with the bomb?’” and I hopped up and I said ‘Yes, it’s right over here,’” Belanger said.

Patti says she was hiding it under a plastic bag on her porch.

“As I pulled it up, he backed off,” Patti said. “He took one look at it and immediately the unmarked cars started showing up.”

And then Patti says the bomb squad showed up.

Lt. Jerry Brewer with the New Hanover County Sheriff’s Office says they determined it is a union 20-pound parrot round from the civil war.

“It was actually live,” Belanger said.

“It’s actually illegal for them to possess it,” Lt. Brewer said. “Any artillery round that hadn’t been disposed of and cleaned out properly is against the law to possess.”

That’s why Brewer says they took it away to discharge it.

“He sent us a picture and said ‘I’m so sorry,’” Belanger said.

Because sometimes making it safe doesn’t always mean keeping it in one piece.

“But I’ll bring you the pieces,” Lt. Brewer told them.

The next day, the Belangers got all the pieces and instructions on how to put it back together.

“It’s a really great story,” Belanger said.

It’s a story about a treasure hunt they didn’t even know they were on.

“Some people who are the Civil War buffs have probably been looking for this all their lives. We’ve been here 3 weeks, and it literally just washed up at our feet. So we feel pretty cool about this whole thing.”

The couple donated the remains of the bomb to the state of North Carolina and it will be on display within six months to a year.