(CNN) A couple searching for shells, artifacts and other treasures on Folly Beach found two Civil War-era cannonballs unearthed by Hurricane Dorian.
Aaron Lattin and his girlfriend discovered the cannonballs on Sunday near a pile of brush on the beach near Charleston, South Carolina.
"At first we just thought it was a rock, but the more we got looking we realized that it was something more than a rock," Lattin told CNN affiliate WCSC.
Lattin said he had wanted to get a metal detector to search for artifacts after Dorian, but they made the find without any equipment at all. The storm swept up the East Coast after devastating parts of the Bahamas.
The couple found an 8-inch cannonball and a smaller 3-inch shell, Chief Andrew Gilreath with the Folly Beach Department of Public Safety told CNN.
They called authorities, who cordoned off the area until explosive ordnance disposal experts from the Charleston County Sheriff's Office and the US Air Force could secure the cannonballs and determine they were safe.
"It took the better part of the day, so I'd say close to six hours or so, give or take," Gilreath said.
People had to keep their distance from the shells, Gilreath said, but it didn't disrupt their day at the beach.
Gilreath said the explosive experts hauled off the cannonballs and that they would probably be destroyed.
Folly Beach Island was occupied in 1863 by Union forces, who built roads, forts, an artillery battery and a supply depot, according to the city's website. At one point, it could hold up to 13,000 troops and their equipment.
It's not far from Fort Sumter, where the first shots of the Civil War were fired on April 12, 1861.
"This is something that's happened every couple of years since I've been here, at least," Gilreath said. "We'll have some erosion on the beach, and something will get uncovered."
Hurricane Matthew uncovered 16 cannonballs on Folly Beach in 2016, which were disposed of by the US Air Force.