Two monuments stacked on one spot
Creggankeel is two sites in one, which is what makes it worth the short walk on the east side of Inisheer. The older is an Iron Age cashel, a drystone fort of the kind built across Ireland after the 1st century BC: two square walls enclosing roughly 30 by 25 metres, the masonry about three metres thick and two metres high, laid without mortar. Inside it sits the younger layer, the Grave of the Seven Daughters (Cill na Seacht nIníon), an early Christian burial ground.
The name comes from the Irish creagáin chaoil, ‘narrow stony place’, and locally the graveyard is also called An Chill Bheannaithe, the blessed graveyard. The site looks out over An Loch Mór, the only freshwater lake on the island.
What you are actually looking at
The detail worth seeking out is in the graveyard walls. The Grave of the Seven Daughters is an incomplete circuit of a cashel, and set into its walls are sleeping niches that have drawn comparisons to the catacombs of early Christian Europe. The burial ground is tied to the female saint Moninne and was established around the 5th or 6th century AD. Among the stones you can pick out a cross-inscribed pillar stone, and the foundations of other buildings, likely a small oratory and a clochán (a beehive-style drystone hut). One nearby structure resembles a site at Cashelmore in County Sligo.
The best single thing to understand here is how the layers connect. In the 15th century the cashel’s walls were robbed for stone and built into the outer walls of nearby O’Brien’s Castle, the island’s tower house. On a place as stony and treeless as Inisheer, a good wall was too useful to leave standing idle, so the fort that defended an Iron Age homestead ended up part of a medieval castle.
Visiting
This is a National Monument in the care of the Office of Public Works, but there is no staff, no ticket office and no set hours: you walk in during daylight, for free. It is exposed to the full Atlantic wind, the ground is uneven and the walls sit on natural rock, so wear something windproof and proper footwear, and don’t expect a wheelchair or buggy route. There are no facilities at the site; the village near the pier has the cafés, toilets and bike hire, and most people get around the island on foot or by bike.
Pair it with O’Brien’s Castle, a few minutes away and built partly from these very stones, and finish with a loop of the lake shore below. Together that is an easy half-day, and it stitches the island’s history into a single short walk.