Cù-sìth
Pronounced koo SHEE — [kʰuː ˈʃiː]
The Green Hound of the Fairy Knolls
“A bull-sized green hound whose three booming barks mean your time is up.”
In the fairy faith of the Scottish Highlands and the Hebrides, the cu-sith is the hound the Good People keep — a dog the size of a young bull, its shaggy coat a dark and unnatural green, its long tail coiled or plaited on its back like the straw rug of a pack-saddle. It hunts in silence across the moors, gliding rather than running, and it leaves footprints in mud and snow as large as the spread of a man's hand.
What makes the cu-sith feared is not its bite but its voice. Tradition holds that the beast bays only three times, with long intervals between, a clamour that carries for miles and has been heard far out at sea. Anyone abroad on the moor when the first bark sounds must reach safety before the third — those who fail are overtaken and destroyed by sheer terror. In a landscape crowded with black-dog omens, the green hound stands apart: not a devil's dog, but the fairies' own.
The Legend
The cu-sith belongs to the sith, the fairy folk of the Highland hills, and serves them as watchdog and enforcer. It dens in the clefts of rocks and roams the open moor, always travelling in a straight line, silent until it chooses to be heard. Islanders described its deep-green ears and a coat that lightens toward the feet — details precise enough to suggest generations of tellers who believed they were describing something seen.
Its errands were dreaded. The hound was said to be loosed to carry off nursing mothers, spiriting them into the fairy knolls to suckle the children of the sith. And its triple bark served as the Otherworld's final notice: a warning system with a countdown built in. Crofters listening at their doors knew the rule — bar the door, reach the house, be anywhere but the open moor before the third cry died away.
The Record
The definitive account comes from John Gregorson Campbell, the Hebridean minister and folklorist whose Superstitions of the Highlands and Islands of Scotland (1900) preserved the creature directly from oral tradition. Campbell recorded a dog 'as large as a two-year-old stirk', dark green with deep-green ears, a bark like 'a rude clamour' repeated only thrice, and huge footprints found in mud, snow, and sand.
Campbell also noted the cost of crossing fairy hounds: mortal dogs that chased the fairy folk came home with the hair scraped from their bodies, all except the ears, and died soon after. The cu-sith has close kin across the Celtic world — the Irish cu sidhe and the Cwn Annwn, the hunting hounds of the Welsh Otherworld — but its green coat marks it out as distinct among the spectral dogs of Britain.
The Lore
Green is the fairies' colour in Highland belief, and the hound wears it as livery. Where England's crossroads dogs and churchyard shucks read as devils, the cu-sith is something older and stranger: an agent of a parallel society living inside the hills, with its own laws, cattle, and hounds. Hearing it bay was less a haunting than a border incident — the moment the hidden neighbours turned their attention on you.
The name is plain Gaelic bookkeeping: cu, dog, and sith, of the fairy mounds — plural coin-shith. Fishermen claimed the triple bay could reach them far out at sea, which made the hound a creature of the whole Gaelic Atlantic edge, not merely the moor. Folklorists read it as the wild twin of the fairy cattle said to be kept inside the knolls: proof that the Otherworld, like the crofting world above it, kept working animals.
Field Notes
- ✦ Said to travel in straight lines and hunt in silence across the open moor.
- ✦ Believed to carry off nursing mothers to provide milk for the children of the fairy knolls.
- ✦ An Otherworld death-harbinger, set apart from Britain's devilish black-dog legends by its fairy-green coat.
- ✦ Campbell (1900) recorded footprints 'as large as the spread of the human hand' left in mud, snow, and sand.
- ✦ Its three widely spaced barks were said to carry for miles — even to fishermen far out at sea.
Case File
- Classification
- Spectral Hound
- Category
- Spectral/Undead
- Territory
- Scottish Highlands and the Hebrides
- First Sighted
- Scottish Gaelic and Hebridean folklore
- Habitat
- Moors, glens, and clefts of the Highlands
- Reported Size
- Hound the size of a young bull with shaggy dark-green fur
- Also Known As
- Fairy Hound · Cu Sith