Oweynagat is a hole in the ground at the edge of a field near Tulsk – a low stone opening you crawl through on hands and knees into a tight, pitch-dark fissure in the limestone. Above ground there is almost nothing to see, and that’s the first thing to know: the reward here is the crawl and the stories, not a view. The second is that you can only get inside on a guided tour from the Rathcroghan Visitor Centre, and only between April and October. If you’re claustrophobic, give it a miss – the passage is genuinely narrow and muddy.
What the cave has instead of scenery is a reputation. Medieval writers called it Ireland’s ‘Gate to Hell’, the mouth of the Otherworld. It is the lair of the Morrígan, the shape-shifting war-goddess, and in folklore the source of the creatures that poured out each Samhain and sent people indoors behind lit fires and disguises – the distant ancestor of Halloween.
The stories
Oweynagat (Uaimh na gCat, the Cave of the Cats) sits inside Rathcroghan, the sprawling royal complex of County Roscommon that was the seat of Medb, the warrior queen of Connacht. The cave runs all through the early Irish tales. In the Echtra Nerai, the warrior Nera follows a host of the dead into the cave on Samhain night and comes back with a vision of the burning of Cruachan. The Morrígan is said to ride out of it, and from here came the otherworldly cow whose calf grew into the Brown Bull of the Táin Bó Cúailnge, the prize at the centre of Ireland’s oldest epic. One local legend even has the cave connecting underground to the caves of Kesh in Sligo – discovered, the story goes, when a calf dragged a woman the whole way through.
Inside the cave
The entrance is a man-made souterrain – about 10.5 m of drystone walling, upright slabs and lintels – built over the natural cave mouth, its covering mound mostly lost when a farm track was cut through. Beyond it the natural limestone fissure runs on for roughly 37 m and drops about 7 m below ground, narrow but high, around 2.5 m wide.
Two of the lintel stones carry Ogham, the rare survival that makes the cave matter to archaeologists as much as to storytellers. One reads VRAICCI MAQI MEDVI – ‘of Fraech, son of Medb’ – tying the stones straight back to the cave’s legends. A second, fragmentary inscription, QR G SMU, has never been deciphered. As one writer put it, you crawl in through a low gap in a field and come out somewhere older than the pyramids: not for the claustrophobic, but extraordinary. The black cat of the name lives on as the site’s modern emblem rather than a real doorkeeper, so don’t count on a welcoming committee.
Seeing it: tours and access
The cave is on private farmland, protected under the National Monuments Act, so the way to see it is the guided tour from the Rathcroghan Visitor Centre in Tulsk, which runs a minibus out to the cave and the great Rathcroghan Mound. The Origins of Samhain – Oweynagat Cave Tour lasts about two and a half hours and pairs the archaeology with the mythology.
One booking tip that matters: in high summer (May to August) only the 14:00 tour actually goes inside the cave, so if going down is the point, book that one. Tours run April to October, with a special tour on Samhain itself, 31 October; the local guide Mike Croghan also runs trips. Wear wellies and bring a head torch – it’s wet underfoot and there is no light inside.
Practical information
- Access: Inside only on a guided tour (April–October) booked through the Rathcroghan Visitor Centre, Tulsk. The surrounding Rathcroghan monuments can be visited more freely.
- Admission: No charge for the exterior landscape; the visitor centre and guided tours carry a fee – check current prices when booking.
- Fitness and accessibility: Not suitable for anyone with mobility difficulties, and a tight squeeze even for average-sized adults. The initial passage requires crawling.
- Getting there: The visitor centre in Tulsk sits on the N5 between Roscommon town and Strokestown; Bus Éireann route 22 stops in the village, a short walk away. Tours shuttle you out to the cave from there.
- Café: The Táin Café at the centre does light meals. Look out for Black Donkey Brewery’s Underworld Savage Ale, brewed with wild yeast swabbed from the cave’s own walls.
Nearby
- Rathcroghan Mound – The flat-topped ceremonial earthwork at the centre of the complex, included on the guided tour.
- Carnfree – The inauguration mound where the kings of Connacht were crowned, another of the complex’s monuments.
- Boyle Abbey – A well-preserved Cistercian ruin on the River Boyle, about 20 minutes’ drive.
- Castlecoote – A 17th-century manor house with gardens, roughly half an hour away.
If going underground is the point, book the 14:00 tour in summer, pull on the wellies and bring a torch. And don’t waste an afternoon trying to find the cave on your own – from the surface it’s a gap in a ditch, and everything that makes it worth the trip is locked up in the dark and in the guide’s telling.