Blog · Course guide · 30 October 2026

Granite Peaks 100K: a section-by-section course guide

The Granite Peaks 100K is essentially one giant loop of the Mourne Mountains, entirely on open mountain terrain. It starts at 6pm on Friday 16 April 2027 from Shimna Integrated College in Newcastle, runs through the night, and has a 29-hour cut-off.

This guide is written from years of running and training in these mountains. It covers what each section is like underfoot, where it's harder than it looks on the map, where you can make up time, and how to pace it.

A few things are true of the whole course. Mourne granite grips well when it's dry, but wet rock, wet grass and peat are a different story, and the weather can change quickly. Much of the route is on rough mountain ground rather than made paths, and a lot of it is covered in the dark. None of that should put you off. It just means the runners who do well here are usually the patient ones, not the fastest.

Aid stations and cut-offs

Cut-offs are clock times for a 6pm Friday start. There's also an optional 5pm early start for non-competitive runners, who opt in by email. The cut-off clock times stay the same, so early starters get an extra hour.

The minimum pace for each section below is the average you need to reach the next aid station before its cut-off. It includes your time stopped at aid stations, so aim to be well inside it. Don't read too much into the numbers on their own, though: a 15-minute kilometre on a good trail is very different from one through bog in the dark, which is why the ground is described for every section.

Every aid station has food and drinks. The race is cup-free, so a collapsible cup is on the mandatory kit list: keep it somewhere you can reach without taking your pack off.

Most runners will cover sections 2 to 4 entirely in the dark, around 10 hours of night running, and anyone still out after about 9pm on Saturday will need their head torch again.

Section by section

You start climbing almost straight away: about 830m up Slieve Donard, Northern Ireland's highest mountain, at an average of around 12%. It's a long, sustained climb, and with a start-line crowd around you it's very easy to go up it faster than you should. You'll have the best of the evening light on the way up, and on a clear night the views back over Newcastle and Dundrum Bay are worth a look.

The ground coming off Donard onto the Brandy Pad, the old smugglers' path that runs through the heart of the high Mournes, is rough and technical: loose rock, steps and awkward footing. Take your time here; there's no prize for being first onto the Brandy Pad. Once you're on it, the going to Cove Mountain is good, and you can settle into a rhythm.

From Cove down to the Annalong Valley aid station the ground can be wet and boggy underfoot. It's the kind of descent that catches people out because it comes early, when they still feel fresh and want to push on. Be careful, keep your weight over your feet, and don't worry about the time.

Coach's notes: this is the biggest climb of the race and it comes first, on fresh legs and adrenaline. Hike it at an easy, conversational effort. If you're breathing hard on Donard, you're going too fast, and that will cost you far more later in the night than you'll gain now. Have your head torch somewhere easy to reach: the light will be going during this section or soon after, and it's much easier to put it on before you need it.

A tough section with three big climbs, almost all of it in the dark. It's also one of the most dramatic parts of the Mournes, so if you've recced it in daylight, you'll know what's around you.

• Slieve Binnian: a tough climb out of the Annalong Valley, at around 15%. Binnian is known for its granite tors along the summit ridge. The reward for the climb is a beautiful new trail as you descend off Binnian's North Tor towards the Ben Crom dam. It's one of the nicest bits of descending on the course, so enjoy it, but stay in control: there's a lot of night still to come.
• Doan: the climb from Ben Crom to Doan is heathery and pathless in places. This is where you need to follow the GPX and the route markers carefully, especially if there's mist. The descent off Doan is steep and broken, and the best line can be tricky to find. If you're not sure, stop, check your watch and look for the next marker. A few seconds checking is much quicker than a wrong turn.
• Slieve Muck: once you're down by Lough Shannagh, the trail gets a bit nicer, but loose stone makes it tricky to run at night. Then comes the climb up Muck: the steepest on the course, at over 20%. It goes on for a while, and it will feel very tough. Put your head down, keep moving, and remember you're nearly at the second aid station.

Take care on the descent to Deers Meadow, the steepest of the race at close to 30%. It can be very slippy when it's wet, so pick your way down. The lights and noise of the aid station are a welcome sight at the bottom.

Coach's notes: be patient and navigate carefully. This section is more about care than speed: poles help a lot on Binnian and Muck, and on the steep, loose descents, short steps and a good head torch matter more than pace. Deers Meadow is the first place you can see your crew. Have a plan for what you need from them, so you can get it and keep moving.

From Deers Meadow you're heading into the toughest part of the race: the whole stretch to Rostrevor. It may take longer than you expect, so it's worth knowing that before you leave, and setting off with plenty of food and water.

This first part is the kindest of it. After the climb over Slievemoughanmore, the descent to Sandy Brae is lovely: a beautiful valley deep in the Mournes, quiet and remote, a long way from any road. Even in the dark you'll get a sense of how far into the mountains you are.

Coach's notes: enjoy this descent and let it settle you, but don't be fooled into thinking the hard part is over. Eat and drink well on the way down and at Sandy Brae, because the next section is the hardest of the night. The cut-off window to Sandy Brae is one of the tightest, so keep moving steadily rather than lingering. Head torches are checked at the start and again at Sandy Brae, so make sure yours is working and your spare batteries are with you.

The longest section and the hardest, in the quieter Western Mournes. The course is marked where there's no obvious path, but there isn't always a good path to follow, and you'll still need the GPX: expect bog and tussocky, uneven ground. It's also where you'll be at your lowest point of the night, physically and probably mentally, in the hours before dawn.

The climb up Eagle Mountain is one of the highlights of the whole route. On a clear night you'll see a line of head torches stretching the whole length of the climb, in front of you and behind you. It's a good reminder that everyone around you is going through the same thing.

From Eagle to Shanlieve is tough going, and then comes the hardest descent of the race. Off Shanlieve it gets slippery, and at the bottom there's waist-deep bog. Follow the markers and the GPX, but don't expect a clear line: there's no easy way through. It's just difficult ground. Go steadily, test your footing, and use your poles if you have them. Expect to get wet. Keep going: once you're through the bog, you're nearly on good ground.

From there it's a lovely trail to Slieve Martin, the mountain above Rostrevor and home to the Cloughmore Stone, and you can finally run if you still have the legs. Then it's a steep drop down into Rostrevor, the lowest point on the course, close to sea level by Carlingford Lough.

Coach's notes: if you arrive at Slieve Martin feeling fresh, you're in a good way, and that's the real test of how well you've paced the first half. If you don't, that's normal too: almost everyone has a low patch somewhere in this section. Keep eating on a schedule even when you don't feel like it, because a lot of low patches are really just low energy. Rostrevor is the first drop bag. Plan what you'll change and eat before you arrive, so you're in and out quickly. Many runners will reach it around dawn, and the daylight makes a big difference to how you feel.

The most runnable part of the race, and after the night you've had, it feels like a reward. Rostrevor to Leitrim Lodge is predominantly good, beautiful running, and by now everyone will be in daylight. A long, gradual climb of about 440m at around 4–5% takes you up to Pierce's Castle, then down to Leitrim Lodge. On a clear morning you'll get great views back over Carlingford Lough.

Coach's notes: this section has the tightest minimum pace, but it's also the most runnable, so the two usually balance out. If you've paced the night well, run the gentle gradients rather than hiking them, and use the lift that daylight brings. If you're struggling, run–walk it: a steady mix of running and walking adds up quickly on ground this good.

A varied section with plenty to enjoy. It's good ground up Rocky Mountain from Leitrim Lodge, then down the Mourne Way to the bottom of Hen Mountain, a stunning little rocky mountain with granite tors on top. It's small compared with what you've already climbed, but it's one of the best spots in the Mournes.

After that, there are some fun, punchy climbs: up Cock Mountain, then down to Spelga, where you cross the road at the dam car park. The climb up Butter Mountain is easy by the standards of this course, and the descent to the Ott aid station is nice running. There's another road crossing at Ott.

Coach's notes: a generous cut-off window, so this is a good place to deal with any problems before they get worse: feet, chafing, stomach. The short climbs come quickly, so take each one as it comes and don't try to rush them. Ott has your second drop bag: a good time for fresh socks, to restock for the final 21km, and to have your head torch ready in case you finish in the dark.

You're nearly there. The trails from Ott to Meelmore Lodge are mostly very good, apart from the high section over Slieve Meelbeg, Slieve Meelmore and Slieve Bearnagh, which can be very hard on tired legs. These are three proper mountain tops in quick succession, and after 80km they'll feel bigger than they look. Bearnagh, with its granite tors, is one of the most striking mountains in the range, so it's worth lifting your head for the view.

Coach's notes: after 80km, these three tops can feel relentless. Break it into one summit at a time and don't think about the next one until you're on top of the one you're on. Save something for the descent off Bearnagh: tired quads, steep ground and a loss of concentration late in a race are when most falls happen. Meelmore Lodge is your last aid station, and it's the last chance to see your crew before the finish.

The final section is beautiful, and a fitting way to finish. From Meelmore Lodge you climb the green ramp towards Slieve Commedagh, about 560m up, the second-highest point of the course. It's a long climb at the end of a long race, but it's steady, and the higher you get, the more of the course you'll be able to see behind you: most of the Mournes you've just run around.

Then it's downhill all the way, about 740m, back to Newcastle and the finish, where there's hot food and drinks and your finish bag waiting.

Coach's notes: the cut-off is generous, so if you've made Meelmore Lodge in time, you've almost certainly got the time to finish. The challenge is the long descent on very tired legs, possibly in the dark again. Have your head torch ready before you leave Meelmore Lodge, keep eating, and stay careful right to the bottom. It's a long way down, and the last few kilometres are no place for a fall.

Kit

All 100K runners must carry the full mandatory kit list for the whole race, including two head torches (minimum 200 lumens, with spare batteries), waterproof jacket and trousers with taped seams, a warm layer, hat and gloves, a foil bivy bag, a collapsible cup and at least 1.5 litres of water capacity. Kit is checked at registration and may be checked on the course. If the forecast is cold or hot, extra kit may be required, and you'll be told before registration opens.

A few things from experience:

• Plan for a cold night. April nights on the tops can be close to freezing, especially in wind or mist, and you'll be moving slowly on the climbs. Have your warm layers where you can get them quickly.
• Carry enough water for the long sections. Sandy Brae to Rostrevor is 17.8km and can take well over four hours at night. Leave Sandy Brae with your bottles full.
• Poles are allowed, and most runners will find them useful on the steep climbs and the bog. You must carry them for the whole race, they can't go in a drop bag, and you can't use them at the start, the finish or inside aid stations.
• Navigation. The course crosses open mountain, often away from paths, and mist and low cloud are common in the Mournes. You must be able to follow the GPX on a watch or phone, and recceing the course, especially the night sections, is strongly recommended.

Crew, companions and race rules

Crew can meet you at Deers Meadow, Rostrevor, Leitrim Lodge, Ott Car Park and Meelmore Lodge, and nowhere else: help anywhere else on the course isn't allowed. Make sure your crew knows there's no mobile signal at Leitrim Lodge or Ott, and only patchy signal at Meelmore Lodge on some networks, so agree a plan in advance rather than relying on texts. Parking at Leitrim Lodge and Ott is limited, and there's a £4 charge per car at Meelmore Lodge. The race website has a full crew guide.

Companion runners. If you'd rather not run the night alone, you can bring a companion from the start to Rostrevor, free of charge. They must be named by the entry closing date (31 March 2027), carry the full 100K kit and stay with you the whole way. They can't pace you, navigate for you or carry anything for you, and runners with a companion aren't eligible for a podium place.

Other rules worth knowing:

• Registration and kit check for the 100K is from 4pm to 5:45pm on Friday. There's a compulsory race briefing 15 minutes before the start.
• No headphones or earbuds.
• Follow the GPX. Short-cutting gets a time penalty.
• Runners don't have right of way at the three road crossings: Deers Meadow, the Spelga Dam car park and Ott Car Park.
• Dropping litter means disqualification.
• If another runner is in difficulty, stop and help. Your cut-offs will be extended for the time you spend helping.

If you need to stop, tell a marshal at the nearest aid station before you leave the course. Walking off the mountain without telling anyone triggers a search. Transport back to Newcastle is arranged from any aid station with road access.

How to train for it

To enter, you need to have completed an ultra of 50K or more with 2,000m+ of climbing in the last 3 years, or have equivalent mountain experience. Beyond that, focus on:

1. Long days on steep ground. Back-to-back long runs with plenty of climbing and descending.
2. Power hiking. Most of the big climbs here are steeper than 10%, where hiking is often as fast as running.
3. Descending and technical ground. Train your quads for repeated steep descents, and practise on loose, wet and boggy ground. The Shanlieve descent and the drop to Deers Meadow are the trickiest.
4. Night running. Practise on trails and open hillside with your race head torch.
5. Fuelling. You'll be out for many hours. Train your gut to take in food regularly (see our gut training summary).

Our guide to training for your first trail 50km covers the basics of building up to a mountain ultra.

Distances, cut-offs and aid station details are from the official race website. Section climbing, gradients and high points are approximate, measured from the official GPX. Always check the race website for the latest information.