A group of students from the King's former school have discovered the remains of what is thought to be a medieval Viking church on an uninhabited Scottish island.
The Gordonstoun pupils made the discovery during an archaeological field trip to Swona, a tiny Orkney island where only feral cattle live.
The building is said to bear similarities to other Viking churches from the 10th and 11th centuries.
Students and staff from the private school in Moray, which King Charles attended, worked with experts from the Orkney Research Centre for Archaeology (ORCA) to uncover the remains during a recent six-day trip.
The visitors stayed in an abandoned house which had not been lived in for a century, with no electricity and fresh water pumped from an ancient well.
The remains of the church, including what is thought to be the foundation for its altar, were found beneath a more recent building on the island.
It is hoped that the radiocarbon dating of samples taken will offer more conclusions about the structure.
The trip to Swona was organised by Dan McLean, a housemaster at Gordonstoun supporting pastoral care for the students.
He said: "The only real hint about a church being on the island is a map reference to a ruin known locally as the 'Twinly Kirk'.
"Once I had identified the site, it first appeared that the remaining church walls were of a more recent building, as they have been added to over the years.
"However, after we worked with the archaeologists to dig a test pit and clear away the weeds, we discovered a step just under the surface, leading to what would have been the church's altar.
"There are other clues, such as the construction method, layout and orientation.
"Another clue was that it was dry stone, and there was no clay bonding or mortar. There are also cairns nearby and a wall that blocks access to a landing point.
"It was a special moment to confirm to the students that they had helped to uncover a piece of Viking history that could be up to 1,000 years old."
Ten pupils took the 10-hour trip to reach Swona, which is about seven miles north of John O'Groats.
Some of them also took part in restoration work on the island, replacing the flooring of the old crofting cottage in which they stayed.
The youngsters explored a probable prehistoric settlement in the centre of the small privately-owned island, and a circular ditch believed to have been the site of a Viking warning beacon.
Student Archie Maclean, 17, said being able to "discover history in real time was incredible".
Fellow pupil Iona Fell added: "What I enjoyed most was the strong sense of community within the group and how quickly we became a team."
Paul Clark, ORCA's senior project manager, said the children showed "great enthusiasm".
He added: "The next step is to look at the samples we took, to see what they can tell us about the activity undertaken at the chapel, and hopefully recover material suitable for radiocarbon dating."
(c) Sky News 2026: Gordonstoun School pupils discover '1,000-year-old Viking church'

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