YOU know the story of Roswell, New Mexico, where locals claim to regularly see alien aircraft flying around what is now known as Area 51.

But in 1974 Wales had its own UFO incident, which many have called the “Welsh Roswell”.

This was the Roswelsh Incident.

There was a huge bang and a brilliant light over the Berwyn Mountains, and there were later claims a spaceship crash was concealed.

This is similar to the Roswell story, where locals and alien conspiracy theorists around the world claim that the American officials took the crashed UFO for examination and investigations.

However, these claims were denied by the Ministry of Defence.

A search and rescue team was scrambled from RAF Valley on Anglesey, but found no wreckage on the mountainside.

The National Archives files show it was explained by a noisy earth tremor coinciding with a meteor burning up in the atmosphere.

The MoD investigation found that there were five other reports of UFOs seen over the UK at about 10pm on January 23rd 1974, when the Berwyn Mountains incident happened.

Of these, three sightings were in the Home Counties, one in Lincolnshire and another in Sussex.

Witnesses reported seeing a bright light in the north west which seemed to fall towards the horizon.

An expert who undertook independent research into the Berwyn Mountains incident for the British Astronomical Society reported that a “fireball” was visible over most of the UK that night.

Sightings were received from Somerset, Norfolk, Manchester and Edinburgh, the files notes. The fireball descended from about 120km in the sky to about 35km before disintegrating over Manchester, the expert found.

Brynmor John, who was then junior RAF minister, explained the official position in a letter to Dafydd Elis Thomas, then a local MP, in May 1974.

Mr John wrote: “As suggested by the descriptions reported, it seems the phenomena could well have been caused by a meteor descending through the atmosphere burning up and finally disintegrating before it reached the ground.

“Such a hypothesis would also explain the absence of any signs of impact.

“It has also been suggested that at 8.32pm that evening there was an earth tremor in the Berwyn Mountains which produced a landslide with noises like detonation.

“The latter aspect is however outside the field of this department,” Mr John added.

But the MoD’s conclusions did not convince all those who witnessed the “Welsh Roswell”.

The files also include a letter from one local who wrote: “That ‘something” came down in the Berwyn Mountains on that night I am certain.

“It is certain to the minds of both my friends who came with me and to me that we were visited by an object that evening.”

Huw, then 14, had been watching television with his two older sisters and a neighbour when their hillside home in North Wales was rocked by a “violent thud” that knocked him from his chair. Within minutes four police officers were at his front door, asking if his father could drive them into the inhospitable Berwyn Mountains in a farm vehicle.

The officers claimed a plane had crashed.

Within minutes he was at the wheel of his dad’s Land Rover, driving the officers through the gloom.

Huw said: “Our neighbour, a retired RAF officer, sat in the —passenger seat and the policemen were in the back.”

As the Land Rover nosed carefully along the track that wound through thick forests and bogs, the officers kept colleagues informed of their progress via their radios. Meanwhile, Huw began to prepare himself for the grim scene that might lie ahead.

“I was expecting we’d find a blazing aircraft with bodies strewn among wreckage,” he said, when they were “blinded” by the brightest light Huw, now 51, has ever seen.

“It must have been about 30 minutes after the explosion we’d heard while we were in the house. Suddenly the whole sky was lit up by the most incredible white light, brighter it seemed than even the sun. For close on 30 seconds the skies were filled with this light for as far as you could see.”

The awed youngster quickly composed himself and pressed on, only for the 4×4 to get stuck in a bog. The officers got out to free it but when they had done so and got back in, one of them said quietly: “Take us back down the mountain, please. We’re done here.”

Huw said: “Surely they could have made it to the scene on foot. I estimated we could only have been a few hundred yards away by then.”

“Looking back, as I have so many times, I think the officers must have taken a message over their radios telling them to back off, for reasons I can only guess at. They certainly didn’t want to talk to me about it that night. We drove back down the mountain in silence.”

One UFO specialist, Russ Kellett, who has spent the past 23 years investigating such incidents after his own “close encounter” believes he has uncovered evidence that the MoD could have been searching for crashed alien craft on that night.

Russ said: “The Photoflash operation was used to light up the coast so they could see submerged UFO craft in the sea.

“I believe there were three separate craft that were flushed out of the ocean that night, military craft were involved and there was an engagement.

“I spoke to a fisherman who saw one come out near Puffin Island. His colleagues at the time told him to say nothing about it because it was considered bad luck. He never spoke about it for years.”

What happened on the Welsh hills we’ll probably never know – but many locals to this day will insist that an alien spaceship was flying around all those years ago.