A team of Castlereagh scuba divers were astounded to find two Elizabethan cannon in the waters of Larne Lough almost 30 years ago.
And that was the last they saw of the artillery – until now.
The solid bronze armaments carrying the crest of Elizabeth I may have been cast to fight in the Spanish Armada. They were found by members of the Castlereagh branch of the British Sub-Aqua Club (BSAC) in 1985 when they were searching for scrap metal to rise much-needed funds.
In line with salvage legislation, the divers sold the cannon to the Ulster Museum after bringing them to the surface. And that was the last they saw of them until a fellow club member stumbled across one of the 7ft 8ins long guns on show at the Boyne Centre in Drogheda.
Randal Armstrong (63), who chaired the group for 15 years, described how they had planned to salvage old chains left behind by the Navy in World War II to sell as scrap metal and raise cash to replace the club's elderly inflatable craft and to buy training equipment – but found something much more valuable.
The guns were lying about 15ft apart and initially the club members thought they had found the deck of a wrecked warship.
Randal said: "When I first went down I thought the others were mistaken, because to me it looked like an old cast iron gas lamp-post, but when I stepped back to get it into shot I stumbled across the other cannon. They were lying parallel to each other, which was very unusual.
"Our Chinook dive boat towed the cannon to the nearest beach where it took 10 of us to lift them into the boat, with much puffing and panting littered with a few swear words."
Mystery still surrounds how the cannon came to be lying on the lough bed, as there is no trace of an accompanying ship.
Randal contacted the official Receiver of Wrecks and within a week the cannon had been moved to the Ulster Museum.
Lawyers worked with the club to prove salvage rights, as another diver who had found an older cannon nearby, bearing the crest of Queen Mary, tried to lay claim to the site.
In 1987 the Receiver of Wrecks paid the club £13,000 and the cannons were handed to the Ulster Museum.
One of the divers, Simon Cosbey, was visiting the Battle of the Boyne site when he saw the cannon, on loan from the museum.
Olwen McConnell, the current club secretary, then contacted the Ulster Museum to see if it was possible for those who discovered and raised the cannon to see the one held in storage again.
In March the divers met Ulster Museum curator Fiona Byrne and travelled to its secret storage location to see the ancient artefact.