The Cat Monster of Dearc Fhearna
Luchtigern — the Mouse Lord, or Lord of Mice — was a monstrous supernatural cat that lived in Dearc Fhearna, the Cave of the Alders, which is now known as Dunmore Cave in County Kilkenny. The Book of Leinster records that an amazon warrior named Aithbel went into the cave and killed it.
The cave itself is real — a limestone cave 11 kilometres north of Kilkenny city, with passages that go down 150 feet into the earth. It is listed in the Triads of Ireland as one of the three darkest places in Ireland, alongside the caves of Knowth and Slaney. Those who named it one of the darkest places in Ireland were not talking about the geology.
Aithbel was a woman warrior — the kind of fighter the Irish called a banghaiscioch, a female champion. She went into the cave and killed the creature that lived in it. The account survives in the Book of Leinster, one of the great medieval Irish manuscripts compiled around 1160.
The cave’s dark reputation did not end with the Luchtigern. In 928 AD, a Viking force under Godfrey, grandson of Ivar, attacked the area. A thousand people fled into Dearc Fhearna to hide. The Vikings found them, lit fires at the entrance to drive them out, took the men as slaves, and left the women and children inside to die. The human bones of forty-four people — mostly women and children — have been found deep in the cave. The Triads’ description of it as one of the darkest places in Ireland proved accurate in every possible sense.
Key facts about Luchtigern
- Name: Luchtigern (“Mouse Lord” or “Lord of Mice”)
- Type: Monstrous supernatural cat
- Location: Dearc Fhearna — Dunmore Cave, County Kilkenny; one of the three darkest places in Ireland
- Killed by: Aithbel — a female champion, recorded in the Book of Leinster (c.1160)
- Cave: Still exists; 11km north of Kilkenny; 150 feet deep; open to visitors
- Historical note: The same cave was the site of a Viking massacre in 928 AD in which 1,000 people sheltering inside were killed
- Division: Ancient — recorded in the Book of Leinster
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