Unexploded mortar shell from bloodiest battle in country's history unearthed after nearly 280 years

The National Trust for Scotland (NTS) announced in mid-April that its archaeologists had found a mortar shell at Culloden Battlefield, just outside Inverness in the Scottish Highlands.

The Battle of Culloden was fought on April 16, 1746, when a Jacobite force led by Charles Edward Stuart - known as Bonnie Prince Charlie - clashed with troops loyal to King George II.

Officials believe that the recently uncovered shell was fired by government artillery during the battle.

"Intact and gunpowder-packed when it was discovered, the 5.5-inch shell is the first piece of complete government ordnance found at Culloden battlefield. [It] provides fresh evidence for the deployment and action of government and Jacobite forces at pivotal moments in the battle," the statement said.

The shell, weighing nearly 18 pounds, is believed to have been fired from one of the government's Coehorn mortars.

Other projectiles, including pistol shot and lead musket balls, were also found.

"Parts of the battlefield are on boggy ground, and it is thought the shell landed on wet ground and the fuse extinguished before it could ignite the powder," noted officials.

Officials said that, once the black powder in the shell was exposed, there was a "slight exothermic reaction."

A specialist "safely cleaned out the interior of the shell, preserved samples of the contents for further study, and certified the shell as free from explosive hazard," the release noted.

In a statement, the NTS's head of archaeology, Derek Alexander, called the discovery a "remarkable - dare I say, explosive - find of the kind archaeologists dream of, but never expect to encounter." 

"Along with the other projectiles recovered, this discovery helps us better understand the formation of troops and concentration of fire during this brief, but brutal, battle," said Alexander.

"The mortars may have been aiming at the Jacobite artillery, so the place where the shell landed may mark the heart of the Culloden battlefield."

An NTS official told Fox News Digital the shell was buried nearly a foot underground - something only professional archaeologists could uncover - and that the site remains safe for visitors.

The discovery comes just months after officials announced a similar find at the same battle site.