Overview
Sliabh an Iarainn (Irish for “iron mountain”) dominates the landscape east of Lough Allen in County Leitrim, reaching an elevation of about 585 m. Part of the Cuilcagh range, the hill is cloaked in heather‑covered moorland, steep grit slopes and a peat‑bog plateau that culminates in a triangulation station offering panoramic views of Lough Allen, the Cuilcagh Mountains and the distant Arigna range. The mountain’s name reflects the rich iron‑ore deposits that were mined here from the early 1600s, shaping the social and industrial fabric of the region.
History & Mythology
The geology of Sliabh an Iarainn stretches back over 300 million years. Carboniferous shales and sandstones record a continuous marine sequence that has yielded an extraordinary array of fossils – goniatites, bivalves, trilobites, brachiopods and occasional echinoids. Patricia Yates documented nearly 120 fossiliferous sites in 1962, many now housed in museums across the UK and Ireland.
Iron extraction began in the early 17th century. Works such as the Cornashamsoge furnace and the Drumshanbo finery forge turned local ore into pig iron that was shipped from Lough Allen. Production peaked in the 18th century, but deforestation and the depletion of charcoal supplies led to decline, with the last Irish iron works at Creevelea closing in the mid‑19th century.
In Irish mythology the mountain is linked to the Tuatha Dé Danann and the smith‑god Goibniu. The Book of Invasions recounts a divine fleet landing on the summit, and folklore speaks of Gobán Saor, the legendary smith, plying his trade in the mountain’s mines. These tales add a layer of mystique to the rugged terrain.
What to See & Do
- Acres Lake Visitor Centre – Situated on the fringe of Acres Lake, just north of Drumshanbo, the modest building houses a 12‑minute audio‑visual exhibition that weaves together the region’s iron‑and‑coal mining, the historic railway, the Shannon‑Blueway canal and the vibrant musical traditions of the valleys. Large windows frame the lake, making the water itself part of the narrative. Admission is free.
- Interactive displays – Touch‑screen panels let visitors explore the engineering of the narrow‑gauge railway, the mechanics of canal locks, and the step‑by‑step process of turning raw ore into pig iron. A short documentary highlights local fiddlers and singers.
- Acres Lake Boardwalk & Shannon Blueway – A 600 m timber boardwalk runs along the lake’s edge and forms part of the 6.5 km Shannon Blueway trail that links Drumshanbo to Battlebridge Lock. The smooth surface is suitable for walkers and cyclists, with interpretive signs describing the lake’s formation, native flora and the historic waterway. The boardwalk is also highlighted on the dedicated Acres Lake – Boardwalk and Visitor Centre page.
- Fossil hunting – The lower slopes and exposed shales near the lake provide accessible outcrops where goniatite shells and trilobite fragments can be observed. Collecting is discouraged in protected sections, but guided walks are offered in summer.
- Summit walk – A moderate hike from the lake to the triangulation station traverses peat‑bog plateau, heather moorland and the striking grit escarpment. The summit rewards trekkers with sweeping vistas of Lough Allen, the Cuilcagh Mountains and the rolling drumlin countryside.
- Cultural landscape – The surrounding area contains historic sites such as old smelting works, the remains of the Arigna railway line and traditional music venues, offering a broader context to the mountain’s industrial past.
Getting There
The visitor centre is accessed via the R207 road, a short detour north of Drumshanbo. A small, free car park sits adjacent to the centre. Public transport options are limited; the nearest bus stop is in Drumshanbo, from where a local taxi can be arranged. The boardwalk and exhibition are wheelchair‑friendly, while the summit trail is uneven and best tackled with sturdy walking shoes.
Practical Information
- Location: Acres Lake, north of Drumshanbo, County Leitrim (postal code: N41).
- Opening hours: April – October – Mon‑Sat 10:00‑18:00, Sun 14:00‑18:00; closed November – March.
- Facilities: Restrooms, a small café serving tea, coffee and local snacks, and a gift shop with books on geology, local history and traditional music.
- Guided activities: Summer months feature guided fossil walks and heritage hikes; bookings can be made at the visitor centre.
- What to bring: Comfortable walking shoes, weather‑appropriate clothing (the area can be windy), a water bottle and a camera for the spectacular summit views.
Nearby Attractions
While you’re in the area, consider visiting other Leitrim highlights:
- Creevelea Abbey – Ruins of a 12th‑century Franciscan monastery set beside Lough Gill.
- Drumshanbo – The nearby market town with its famous Shed Distillery.
- Cavan & Leitrim Railway – Heritage railway offering scenic rides through the countryside.
- Battlebridge – Riverside camping, a historic bridge and access to the Shannon Blueway.
- Glencar Waterfall – A dramatic cascade set in a wooded valley.
Sliabh an Iarainn offers a rare blend of natural beauty, geological intrigue and industrial heritage, all anchored by a modern, free‑entry visitor centre that brings the story of Ireland’s iron mountain to life.