Overview
The passage tomb on the summit of Slieve Gullion is the highest in Ireland, and it was built to catch the sun. At the winter solstice the setting sun shines straight into the chamber, the same alignment as Dowth in the Boyne Valley, which makes this roughly 5,000-year-old cairn a piece of deliberate astronomy rather than a random pile of stones. At 573 m (1,880 ft), Slieve Gullion is also the highest point in County Armagh and the centrepiece of the Ring of Gullion AONB.
If you only do one thing here, walk up to the south cairn: the tomb, the summit lough beside it and the view over the ring of hills are the reason the mountain has a reputation. The forest park on the eastern slope is the family day out, and the two are separate outings – the park is at road level, the summit is a half-day climb.
Ancient stones and old tales
The summit cairns
Two cairns sit on the summit ridge. The southern one is a Neolithic passage tomb of about 3500–2900 BCE, the highest surviving passage grave in Ireland, with a corbelled chamber and stone basins; human bone fragments turned up when it was excavated in the 1960s. The northern cairn is early Bronze Age, around 2000 BCE, and holds two cist burials. Both were dug into by American soldiers stationed nearby during the Second World War, which is why some of the chambers look disturbed.
Legends of the mountain
Slieve Gullion is nicknamed the Mountain of Mystery. The Cailleach Bhéara, the hag of Irish myth, is said to live in the summit lake, Calliagh Bherra’s Lough, also called the Lake of Sorrows. In the best-known story she tricks the hero Fionn mac Cumhaill into swimming in the enchanted water; he climbs out an old grey man, which is how the legend explains his white hair. The slopes also turn up in tales of Cú Chulainn, who killed the smith Culann’s hound in the country below.
Geology and the Geopark
Slieve Gullion is the eroded core of a Paleocene volcano, roughly 60 million years old. Around it runs a ring dyke – a near-circular band of harder volcanic rock – which is what gives the district its distinctive rim of hills. The Ring of Gullion was the first ring-dyke in the world to be geologically mapped, and since 2023 it has been part of the Mourne Gullion Strangford UNESCO Global Geopark. Interpretive panels along the forest drive walk you through the volcanic and glacial history if you want the detail on the ground.
What to do in the forest park
The eastern slope’s forest park mixes active play with quiet woodland.
- Adventure Playpark – Slides, climbing frames, a zip-line (the “Slieve Gullion ZIP”), a trim trail, a soft-surface toddler zone, a maze and outdoor gym stations. It has won the Green Apple Environment Award and been recognised at the Northern Ireland Tourism Awards.
- Fionn’s Giant Adventure – A free, mile-long story trail (formerly the Giant’s Lair) through fairy houses, dragons and the Giant’s Table. A printed map is available at the visitor centre. Some of it runs through narrow woodland nooks, so a backpack carrier or sling is easier than a buggy with toddlers.
- Red squirrels – The forest is a red-squirrel stronghold. Early morning and late afternoon near the play area or wildlife pond give the best chance of a sighting; there is no set safari, just patience.
- Courtyard Café and Visitor Centre – The café serves coffee, teas and hot food; the centre stocks maps, books and details of guided geology walks. A wildlife pond sits beside the seating.
- Scenic forest drive – A one-way loop around the eastern slope with pull-in points and long views over the Armagh drumlins. Note it can close in winter when snow and ice make it unsafe.
- Mountain biking – The forest drive is open to cyclists, with a secure bike rack near the café.
- Camping – Small marked pitches are permitted; register at the visitor centre and follow the Leave-No-Trace policy.
Walking the mountain
The classic loop is 13.5 km (9.5 mi), starting and finishing at the Slieve Gullion Courtyard car park. Allow 3–4 hours and about 511 m of climbing. It passes Ring of Gullion Way panels, the south cairn passage grave and Calliagh Bherra’s Lough, and it is well-marked and graded moderate.
One honest caveat: ongoing tree felling to control the Phytophthora ramorum disease can close sections of path at short notice, with signs posted at the affected points, so a stretch you planned on may be shut. Weather on the top turns fast – carry waterproofs, wear proper footwear, and leave the summit lough for looking at, not swimming.
Practical information
- Location: County Armagh, within the Ring of Gullion AONB and Mourne Gullion Strangford Geopark.
- Opening times: Forest park attractions run to the seasonal hours in the front matter; the mountain itself is open access. Check the visitor centre for weather closures.
- Admission and parking: Free on foot or by bicycle. Parking has been charged since 22 April 2024; residents of the Newry, Mourne and Down Council area can apply for a free annual permit covering one of four council parks. Current rates are displayed on site.
- Getting there: The main car park is the Slieve Gullion Courtyard, signposted from the Newry–Armagh corridor. Ulsterbus routes 85 and 86 stop in Newry; from there you need a taxi or community shuttle to the park entrance.
- Accessibility: The visitor centre, café and several paved sections of the trail are accessible. The summit route is steep and uneven and not suitable for wheelchairs.
- Dogs: Welcome on the forest drive and most walking routes; keep them on a lead near wildlife.
- Guided walks: Book geology or mythology walks, and arrange school-group visits, at the visitor centre.
Nearby attractions
- Ardress House – 18th-century National Trust house in parkland.
- Dromintee – Gateway village to the Ring of Gullion, with more walking routes.
- Ballymoyer Woodland – Woodland with historic ruins, good for a longer day.
- Camlough – Lake and river spot for a picnic or a bit of fishing.
Arrive early on summer weekends before the car park fills, and pick up the free trail map at the visitor centre so you are not guessing at the forest junctions.