Overview
Coffins are still ferried across Lough Derg to Inis Cealtra for burial among the ruins – this is a monastic island that never stopped being a graveyard. The name translates as the island of burials, and in English it’s simply Holy Island. It lies about one kilometre from the mainland and two kilometres north-east of Mountshannon, owned by Clare County Council and conserved by the East Clare Heritage Centre. The only way over is by boat, a crossing people have been making for well over a thousand years.
If the history won’t stick on its own, go with the guided boat tour: local historian Ger Madden runs trips daily through the season and knows the stones one by one. Set expectations first, though – there’s nothing on the island itself. No shop, no toilets, no shelter, uneven stony paths. Bring water, a snack, good footwear and a rain layer, and time your visit for settled weather, because the lake calls the shots on when boats run.
A living monastic site
The island’s origins go back to around 520 AD, when St Colum is said to have set up a hermitage here. By the mid-6th century St Caimin (d. 653) had expanded the settlement, becoming Bishop-Abbot of Inis Cealtra and possibly the first Bishop of Killaloe. The site earned a name as an ‘asylum of Ireland’, with a school of learning and a community of scholars and penitents.
Viking raids in 836 and 922 did serious damage, but the community rebuilt each time. High King Brian Boru is credited with having one of the churches built. The complex stayed active into the 13th century, and the churches fell into ruin only gradually after the Reformation – yet the island never lost its religious purpose. It remained a consecrated burial ground, and coffins are still rowed across for interment among the old stones today.
Its pull as a pilgrimage site outlasted the monastery. In 1608 Pope Paul V granted a plenary indulgence for pilgrimage here, making Holy Island one of twelve ‘notable shrines’ in Ireland; up to 15,000 pilgrims a year came until the Great Famine.
Legends and the roofless tower
The island’s most striking feature is its round tower, about 80 feet (24m) tall and completely roofless. Local folklore blames a witch’s curse on the master mason, but Dr Liam de Paor’s excavations in the 1970s found no sign of a conical cap – the tower was probably never meant to have a roof. Ravens nest in it now, and their calls carry across the water.
Other stones carry their own stories. The ‘bargaining stone’ has a central gap where couples once clasped hands to seal a marriage. Shallow bullaun stones, used for early devotions and grinding, lie scattered near the ruins. Tales of hidden souterrains persist locally, though nothing definitive has been dug up.
What to see & do
The layout is simple and the mood does the rest:
- The churches – Ruined stone churches dedicated to St Caimin, St Michael and St Brigid, among others. Sources differ on the count – six or seven – and the island was once known as the Island of the Seven Churches.
- High crosses & holy well – Four high crosses, a holy well and the monastic cell mark the spiritual heart of the site.
- The cemetery – Some 80 recumbent graves with simple crosses. The graveyard is still in use, which gives the island a living quality most ruins don’t have.
- The visitor centre, Mountshannon – The Inis Cealtra Visitor Experience opened in summer 2025 in Mountshannon, with three exhibitions and a café, and free admission. Worth pairing with the crossing for context.
Getting there & practical information
Boats run from Mountshannon Harbour through the season, roughly April to October, with a crossing of five to ten minutes; Ger Madden operates April to September. Fares apply and are best confirmed with the operator when booking – the new visitor centre in Mountshannon is free. There’s free parking at Mountshannon Harbour and at Knockaphort Harbour.
Access is seasonal and weather-dependent, not year-round: conditions on Lough Derg decide whether crossings go ahead. There are no facilities on the island, so come self-sufficient. The paths are uneven and loose underfoot, so sturdy footwear matters. The terrain limits wheelchair access, though guided operators can sometimes make arrangements for visitors with limited mobility if asked in advance.
For families, it’s a gentle introduction to early Irish history – children tend to like spotting the ravens around the tower and roaming the open ruins.
Exploring further
Just across the water, Bishops Island gives another glimpse of early monastic life. A drive west reaches the Cliffs of Moher, a dramatic contrast to the quiet of the lake. For more background, the heritage trails around Mountshannon set up a full day out in County Clare.
Late spring to early autumn brings the calmest water and the longest days. Come in the morning to beat the busiest boats, and book your return crossing when you land so you’re not left waiting when the afternoon wind gets up.