Overview
Of all the Mourne summits, Slieve Martin asks the least of you. From the upper car park at Kilbroney Park the trig pillar is roughly 45 minutes up, and most of that is a stony forest zig-zag rather than open mountain. At 485 m (1,591 ft) it is no giant, but it sits right over the water, so the view down to Carlingford Lough and across to the Cooley Mountains in County Louth is out of all proportion to the effort. If you have twenty minutes and no intention of a full climb, walk to the Cloughmore Stone instead. The summit itself is a flat, grassy dome; the boulder is the more interesting thing on the hill.
History and folklore
The hill and its forest sit on the old Kilbroney estate, owned by the Ross family before it passed to the Bowes-Lyon family, ancestors of the Queen Mother. The quiet of the place got into a young C. S. Lewis, who spent childhood holidays here and later said the view over the lough was his “idea of Narnia” – the reason the lower woods now carry a Narnia trail.
Midway up the southern slopes sits the Cloughmore Stone, a 50-tonne granite boulder perched about 1,000 ft above Rostrevor. Geologists call it a glacial erratic, dropped by the ice; local tradition prefers the version where the giant Finn McCool flung it across Carlingford Lough during a row, pinning a frost giant beneath it. Walkers still follow the old habit of circling the boulder seven times for luck before turning to the viewpoint the locals call Kodak Corner.
Trail options and routes
Three car parks give onto the hill, each a different way up:
- Upper car park – The direct route, and the one to take. Follow the sign for Cloughmore, climb the stony zig-zag through mixed woodland to the col (about 30 minutes), then finish with a short, steep 10-minute grassy pull to the summit trig pillar. Round trip is roughly 3 km and about 1.5 hours.
- Cloughmore car park – A smaller lot higher on the forest drive, beside the Big Stone itself. A notice board maps the quieter Fiddlers Green and Oakwood trails, which loop through old oakwood before joining the main ascent.
- Lower car park – At the park entrance, best if you want the café, toilets, or to add the Fairy Glen walk. Coming up through the forest drive adds around 45 minutes to the round trip.
For experienced hillwalkers, Slieve Martin is the central peak of the Southern Mournes Trio (with Slievemeen and Crenville), a 12 km circuit that needs real navigation once you reach the boggy ground and faint paths on Crenville.
What to see and do
- Cloughmore Stone and Kodak Corner – A short detour off the main trail. The clearing around the boulder is a natural balcony over the lough and Slieve Foye, Louth’s high point, and the best picnic spot on the hill.
- The Narnia Trail – A half-mile family loop through the lower woodland, past carved sculptures, a lamppost, the Beavers’ house and Aslan’s table. The root-crossed ground rules out pushchairs, but children take to it.
- Summit trig pillar and cairn – Beyond the last steep pull, a grassy mound holds the survey pillar, a modest cairn and a bench. On a clear day Slieve Donard and Binnian stand out sharply to the north; on a grey one there is little reason to go past the Cloughmore Stone at all.
- Wildlife and woodlands – The mixed oak and conifer holds red squirrels, jays, woodpeckers and the odd deer. Spring brings bluebells and wild garlic to the forest floor; autumn turns the heather and gorse gold.
- Nearby heritage – A short walk from the lower car park is the Ross Monument, a 19th-century obelisk to the estate’s owners, and the ruined early church holding the bell of St Brónach, which local tradition says has been heard ringing on stormy nights.
Mountain biking
Kilbroney Forest is a national trail centre and one of the busier mountain-biking hubs on the island. The network runs to 27 km of red-grade and 19 km of black-grade trail, both skirting the Slieve Martin slopes, and the four-route “Slieve Martin Slaughter” challenge (Green, Blue, Yellow, Red) stitches together steep forest climbs, open moorland and technical descents. Bike Mourne runs an uplift service from the lower car park, and downhill races are held here each year.
Practical information
- Parking – Both the upper and lower car parks are currently free. Note the change coming: from April 2026 Kilbroney Park may introduce car park charges, with a free annual permit for Newry, Mourne and Down residents. The upper lot is small and the forest drive to it is one-way and narrow, so it fills fast on summer weekends.
- Park hours – The park gates close seasonally: 5pm November to February, 6pm in March and October, 8pm in April and September, 9pm May to August. The lower car park has a café, toilets and play areas; the upper has picnic tables and barbecue spots but no toilets.
- Facilities – Nothing at the summit. The Kilbroney visitor centre and café at the lower car park open seasonally.
- Dogs – Welcome, but keep them on the marked paths in spring to protect ground-nesting birds.
- Best time to visit – Clear days for the view; spring for bluebells; autumn for the light and fewer people. Winter is fine but the zig-zag ices up.
- Safety – The zig-zag is stony and steep, so wear proper boots. Bikers share the upper trails, so keep to the walkers’ path, and check the forecast: Mourne weather turns quickly.
Getting there
- By car – Follow the A2 coastal road from Belfast or Newry to Rostrevor. The lower car park is signposted from the Shore Road; the narrow one-way forest drive continues up to the upper car park.
- Public transport – Ulsterbus route 39 runs from Newry and Belfast to Rostrevor; from the village stop it is about a 20-minute walk to the park entrance.
- Cycling – The Rostrevor to Carlingford Greenway gives a traffic-free run along the lough if you want to pair the ride with the hill.
Arrive before 11am on a summer weekend if you want the upper car park. It is one-way in and there is nowhere to turn if it is full, so a late arrival often means the long approach from the bottom whether you planned it or not.