The nightmare Edinburgh school trip where five pupils froze to death in the Cairngorms

What was meant to be an exciting school trip for Edinburgh schoolchildren turned into a horrifying ordeal in the Cairngorms. The ambitious winter expedition, which would have challenged even professional climbers, ended tragically.

The youngsters were left to freeze to death under deep snow drifts in a tragic and avoidable incident that took place on November 20 and 21, 1971. This event is sometimes referred to as the Feith Buidhe Disaster, named after the remote mountain location where their bodies were discovered.

Five of the six children and an 18-year old-trainee instructor succumbed to the freezing conditions as the weather worsened and snow accumulated around them. One boy miraculously survived, but the rest of the story is grim.

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The journey began optimistically enough, with six 15-year-old students from Ainslie Park School in Edinburgh and their two leaders departing from the Lagganlia Outdoor Centre. They embarked on a challenging two-day winter navigational exercise to cross the exposed Cairngorm Plateau from Cairn Gorm mountain to Ben Macdui.

Laggania provided them with specialised mountaineering equipment such as Icelandic sleeping bags, ice axes, crampons and cagoules. However, they had no experience dealing with the disorientating and severe conditions that can suddenly occur in the high mountains, particularly during winter.

The group had a contingency plan in place due to the uncertain weather forecast: if conditions worsened, they would seek refuge in the high-level Curran shelter, a small stone bothy perched on the mountaintop.

However, as they ascended, a severe blizzard did indeed strike. The group activated their 'plan B' and attempted to locate the shelter, but were unsuccessful due to the blinding snowstorm.

Their leader, 21 year old Catherine Davidson, a final-year student at Dunfermline College of Physical Education in Fife, made the critical decision to establish a forced bivouac (a makeshift camp without tents) on an exposed, high plateau just 500 yards away from the concealed shelter. They ended up stranded there for two nights in unimaginably harsh conditions.

Unbeknownst to Davidson, the location she'd selected was notorious for accumulating vast amounts of snow: it was possibly the worst place to spend the night.

John Duff, the leader of the Braemar Mountain Rescue Team, stated that this decision essentially sealed the group's fate, saying "to attempt a winter bivouac, in a storm, on a Cairngorms plateau, is literally a life or death decision, and a last option".

He also noted that the major error was even contemplating "an appallingly over-ambitious expedition for teenage children."

The group huddled together in sleeping bags and bivouac sacs, taking shelter behind a snow wall they had constructed. Initially, their spirits remained high, with Davidson leading the children in song.

However, as the snow continued to pile up, fear set in as they worried about being buried alive.

They remained stuck in the same spot for the rest of the day. During the night, they spotted flares from a search party who had bravely ventured into the treacherous blizzard in search of them.

Despite their screams for help, they went unheard, their own flares lost in the snow.

The sight of the search party soon disappeared, leaving them alone once again - an experience that must have been utterly disheartening.

"To be honest they were virtually dead before they set off."

Their second night at the bivouac site - Sunday - proved fatal. The children began to show signs of delirium and started dying.

Hypothermia, which causes confusion and drowsiness, can sometimes lead individuals to believe they are overheating, causing them to leave their sleeping bags and hastening their freezing to death.

Davidson managed to survive. On Monday morning, she crawled away alone in a desperate attempt to find rescue, although by this point, several of the children had already passed away.

Davidson was found in a critical condition, her body rigid from the freezing temperatures, as a rescue helicopter from RAF Leuchars spotted her bright orange jacket amidst the snow.

"We didn't realise they were going so high up the mountain. We thought it was just a trip around Lagganlia and back."

The pilot could only decipher three words from her - "Feith Buidhe", "buried" and "burn".

Mountain rescue teams faced a grim reality upon reaching the site, discovering six lifeless bodies buried to varying degrees in the snowdrifts.

One of the children lay under a four-foot snowdrift.

Raymond Leslie, aged 15, was the last to be found, miraculously showing signs of life and was immediately rushed to Raigmore Hospital in Inverness, where he eventually made a full recovery. Tragically, Carol Bertram, Susan Byrne, Lorraine Dick, William Kerr, and Diane Dudgeon did not survive the ordeal.

Sheelagh Sunderland, an 18 year old trainee instructor, also perished on the treacherous slopes.

As darkness fell once more, the grim task of retrieving the children's bodies had to be postponed until the following day.

Braemar Mountain Rescue Team leader John Duff has recounted the harrowing decision to leave two climbers overnight on the mountain, saying: "I decided to leave them in situ overnight," and elaborating on the perilous conditions that made a rescue attempt too dangerous. "We carried them a few yards to a small rise where there was less chance of them being buried deeply, covered them as best we could, marked the site with avalanche probes and made our way off the hill."

Reflecting on the tragic event, Diane Dudgeon's father shared his regret: "We let her go. She was 15 but she had some experience of climbing. Of course we didn't realise they were going so high up the mountain. We thought it was just a trip around Lagganlia and back."

He added, "We didn't know that plan was to spend a weekend on a hilltop in the middle of winter."

The subsequent inquiry in Banff revealed alarming facts, including that the consent form given to parents failed to mention the involvement of winter mountaineering. While the inquiry did not place blame, it highlighted significant misjudgements, with Duff poignantly noting: "To be honest they were virtually dead before they set off. It was simply a badly planned expedition."

"I've spent my life picking up bodies out the mountains, but with children it's different. They were such needless deaths. It was such a terrible, terrible waste of young lives."