Also known as the 'Big Grey Man', Am Fear Liath Mòr is an experience hikers have reported on Ben Macdui, a remote mountain in the Cairngorms of Scotland.

Mountaineers have for decades ^[1], often when hiking alone, reported something which sounded as though "someone was walking after [them] but taking steps three or four times the length of [their] own." These mountaineers are often experienced, and credible witnesses ^[2].

Unusually, there have been no sightings of Am Fear Liath Mòr, only the sound of footsteps following the walker and occasionally a sense of unease, described by Alexander Borthwick in 1939 as “a queer crinkly feeling in the back of my neck” ^[3].

There is mention of photographs of the footprints ^[4], although these have not been located.