The lock, from the 1583 ‘Ann Francis’ shipwreck, was discovered by a metal detectorist on a beach in Wales in 1999
An ancient padlock found on a shipwreck in Wales has finally been unlocked after more than 400 years.
The brass combination lock was part of a treasure cargo stored on the Ann Francis ship, which was wrecked in a storm off the Welsh coast on Dec. 28, 1583.
Over four decades later, researchers finally worked out the four-letter code to crack the lock: ANCE. Researchers cracked the code using CT scanning technology, Cardiff University said in a press release.
“Working alongside specialists at Cardiff University, museum experts used CT scanning technology to examine the lock’s internal mechanism without causing any damage,” the college said. “The scans allowed researchers to identify the correct letter combination and successfully unlock the historic artefact.”
Metal detectorist Peter Hughes discovered the lock on the beach in Port Talbot, a town around 36 miles west of the capital Cardiff, in 1999, per the BBC and The Telegraph. The lock was then acquired by Amgueddfa Cymru and Cardiff University, per the release.
“It was by chance — a day off,” Hughes, 69, told the BBC. “I was walking along the beach with my metal detector on a day off, and I came across a coin. That was the start of a journey that lasted 21 years.”
“I tried to unlock it for about 20 years, I tried moving the dials, finding the right combinations, and I failed,” he recalled. “But with the aid of modern technology we’ve been able to crack what’s like the Da Vinci code, really.”
The Ann Francis was returning to Spain when a heavy storm blew it off course on the evening of Dec. 28, 1583, wrecking it on Margam Beach, near Port Talbot. The ship’s valuable cargo remained buried in the sand for hundreds of years before experts discovered it, per the release.
According to Cardiff University, the lock secured a small treasure chest found near Spanish silver coins and two coin weights recovered from the wreck site.
Dr. David Williams, a research associate at Cardiff University’s School of Engineering, said, “Micro-CT scanning allowed us to look inside the lock without damaging it. By creating a detailed 3D image of the internal mechanism, I could see how the notches lined up with the letters and identify the exact combination.”
“We normally use this technology to study bones and other biological structures, so investigating a 400-year-old padlock was certainly a first for us,” he continued, “‘…Getting the message that we’d cracked it was incredibly satisfying.”
“It’s not every day you get to solve a 400-year-old mystery!” Williams added.
Hughes added of the triumph, per the BBC, “It’s like opening the Ark of the Covenant, and I’m delighted, truly thrilled.”
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The lock is among several artifacts from the Ann Francis currently on display at the National Waterfront Museum in Swansea, Wales, which is just up the coast from where the padlock was discovered.
The exhibition Tides of Treasure runs until September 2027.