Am Fear Liath Mòr

Although there have been many purported encounters with Am Fear Liath Mòr, few eyewitnesses have seen the creature. Those who have describe it as an extremely tall figure covered with short hair, or as an unseen presence that causes uneasy feelings in people who climb the mountain.[2] Other eyewitnesses describe it as a large humanoid standing over ten feet tall and having olive toned skin with long arms and broad shoulders.[3] Evidence of the existence of this creature is limited to various sightings and a few photographs of unusual footprints.[2] Nearly all reports of Am Fear Liath Mòr include the sound of footsteps crunching in the gravel just out of sight.[4]

The summit of Ben Macdui

The first recorded encounter with Am Fear Liath Mòr was reported in 1891 but wasn't made public until 1925.[5] In 1925, the noted climber J. Norman Collie recounted a terrifying experience he had endured while alone near the summit of Ben MacDhui some 35 years before. "I began to think I heard something else than merely the noise of my own footsteps. For every few steps I took I heard a crunch, and then another crunch as if someone was walking after me but taking steps three or four times the length of my own."[2] Collie was unable to make out the source of the noises because of mist, and continued "... [as] the eerie crunch, crunch, sounded behind me, I was seized with terror and took to my heels, staggering blindly among the boulders for four or five miles."

Collie's account was reported in the local press and followed by a correspondence on the subject. Norman G. Forbes reported that he had heard a mysterious clanking noise while climbing Braeriach in summer mist. It proved to be two deer. He noted that the Cairngorms “have an uncanny power of inducing a feeling of eeriness” and "the mind, alone in lonely places, creates many things out of its imagining" .

However, some climbers have also reported similar experiences, many describing uncontrollable feelings of fear and panic, some seeing a huge grey figure behind them, and others only hearing sounds. For example, in 1904 climber Hugh D. Welsh heard unexplained "slurring footsteps" near the summit of Ben Macdhui and had "an eerie feeling of apprehension", while in 1945 Peter Densham, a mountaineer and rescue worker, heard “a crunching noise” and was “overcome by a feeling of apprehension” and in 1948 Richard Frere, a climber, wrote about his sense of “a Presence, utterly abstract but intensely real” on the mountain and heard “an intensely high singing note”.[6]

In 1958, an encounter was published in The Scots magazine by naturalist and mountaineer Alexander Tewnion:

...In October 1943 I spent a ten day leave climbing alone in the Cairngorms... One afternoon, just as I reached the summit cairn of Ben MacDhui, mist swirled across the Lairig Ghru and enveloped the mountain. The atmosphere became dark and oppressive, a fierce, bitter wind whisked among the boulders, and... an odd sound echoed through the mist – a loud footstep, it seemed. Then another, and another... A strange shape loomed up, receded, came charging at me! Without hesitation I whipped out the revolver and fired three times at the figure. When it still came on I turned and hared down the path, reaching Glen Derry in a time that I have never bettered. You may ask was it really the Fear Laith Mhor? Frankly, I think it was.[4]

Illusions, hallucinations or misinterpretation of natural stimulus brought on by exhaustion or isolation have been proposed by psychologists.[7] Infrasound, which can be generated by wind, can cause feelings of uneasiness and anxiety and is possibly connected to paranormal sightings.[8]

An optical illusion known as the Brocken spectre is a plausible explanation for some visual elements of the Big Grey Man legend.[9][10] A Brocken spectre, "mountain spectre" can occur in certain atmospheric conditions when the sun is at a particular angle. The subject's shadow can be cast onto a cloud bank around them, creating the illusion of a large shadowy humanoid figure.[11]

The poet James Hogg encountered a Brocken spectre on Ben MacDhui as far back as 1791, describing "a giant blackamoor, at least thirty feet high, and equally proportioned, and very near me. I was actually struck powerless with astonishment and terror." Hogg's terror subsided when he observed the figure making the same gestures as his own, and he satisfied himself that it was merely his own shadow.[4] British mountaineer Frank Smythe stated he had observed his shadow cast as a Brocken Spectre across the mist on Ben Macdhui.[12]

The creature is referenced in Captive, the first book in K.M. Fawcett's Survival Race series. In the book it's revealed that the Fear Liath is a member of an alien species called Hyboreans.[13]