The Lairig Ghru Race – musings from someone who was beaten by this race – twice!

As so many Harriers have signed up for the Lairig Ghru this year, I felt that my difficult experiences of the two times I tried this race could provide some insight on how you should consider preparing/training for this race.

At 43kms and 680m height gain, it just enters the “ultra” category although it is always defined as a category C long hill race. It is basically a marathon on generally tarmac or forest roads with a modest elevation gain. On paper, it appears “easy”, but there is a gnarly ca. 17 kms middle section between ca. 15 and 32 kms which can be the undoing of many. It is rough, technical and a “normal” fitness for a road marathon will NOT be enough to get you through this section fresh.

In my training, I planned a modest 10kms/hr pace. I would be faster on the road/easy trail sections and slower on the technical sections but hopefully finishing with an average 10k/hr pace – leading to a race time between 4:15 and 4:30. Looking at my pace plot from last year, it is clear that through the technical section, I was woefully slower than this 6 mins/km pace and even after the technical section, my back and legs were clearly gone and I hardly managed to get back to the 6 mins/km pace.

Rob's pace

My Pace plot for 2020 LG race

So – first tip: Don’t underestimate how technical that middle section is. You will be much slower through this section. You must practise running on very technical rocky tracks – WITH tired legs.

Suggestion: Maybe run around the Pentland easy tracks for about 20kms, then do reps on the track on the NW back side of Black Hill between the Green Cleugh and the eastern end of Threipmuir Resevoir.

Running the Stuc O’ Chroin ridge would also be good practise.


Anyway – A quick run down of the route – see numbers on maps below for brief descriptions of sections:

LG – 1st Half

1–2: Nice fast, gentle start on single track tarmac road up the Dee valley. Great views. Under Covid restrictions you will probably be running in groups of 5. This worked very well last year and even if you are ahead, the Dee river crossing at point 2 is very obvious. You cannot go wrong.

2-3: Now on well-maintained tracks and the route takes you through and around the back of the old stables at Mar Lodge. Once on the tracks behind, you need to turn off to the right after about 1.5 kms. I think this was sign posted last year – but there is only one track, so not really an issue I think.

3-4: Straight forward forest track up to the confluence in Glen Derry. There used to be a water station here but under Covid restrictions, I don’t think there will be one. Just after Derry Lodge, you will cross the river on the foot bridge. This confluence is an excellent place to camp.

4-5: My favourite section of the race. Nice bouncy peaty and very runnable track. Alas, this nice running section is only a few kms.

5-6: Now things get tougher. Possible that you will get wet feet crossing the Luibeg burn. In fact, I advise you to just go through and get wet feet rather than trying to skip across the rocks (can be wet and slippy) and risk falling. Once you have crossed the burn, the route starts climbing for the first time. The track now starts getting more technical. Once the track diverts from a westerly to a northly direction you will get your first view of the fabulous U shape valley of the Lairig Ghru. Also – however – you get your first inkling of how long this rather technical section is – it seems to go on forever. Little elevation gain, but a continuous gnarly track. The final 2 kms of this section takes you up towards the Pools of Dee. It is at this point where you will enter the famous granite boulder fields of the central Cairngorms. The good news is that being granite, the rocks are really not that slippy, even in wet conditions. HOWEVER – you don’t want to fall on this stuff, so take it easy. There is not always a clear track through the boulder field, so skipping across rocks, some of which might shift, can be risky if you try it at speed. Remember, you will be at ca. 27 kms at this point, so your legs will be tired and might not function how you want them to.

LG – 2nd half

6-7: Slightly steeper descent after the divide but the path is still annoyingly technical, and I have found muscle cramping a problem here. These few kms seem to go on and on but the terrain/path steadily gets easier.

7-8: As the route leaves the open hillside and enters Rothiemurchus forest, the trail becomes a nice forest track although be careful of roots. This is another section that is really quite pleasant to run down even if your legs are rubber by this point.

8-9-10: When you leave the fell track and hit the forest trail in Rothiemurchus. FFS, turn left! Right goes to Loch Morlich!! This section is pleasant with the river on the left. Just to remind you how tired you are, there are some Himalayan large steps up over the footbridge over the river which normally you would skip up. You will groan as you lift your legs up. But soon after the bridge there will be a fork in the track. Go right and then stay on this easy flat gravel track all the way to Coylumbridge. On a hot day, the shade from the pine trees can be a blessing, but the track does go on and on.

10-Finish: Coylumbridge to Aviemore all pavement beside the road. As I hate road, this final 3 kms always felt endless. Note that my map for last year might not be quite right for the final km or so. Read carefully the instructions for how you are to cross the railway and enter the main street in Aviemore.


Last year, the conditions were almost perfect. The winner came in at 3:03 which might give you an idea how much slower the LG is compared to a normal marathon. My two times were 4:49 and 4:48 – at least 20 mins slower than I would have liked but both times it took me weeks to recover and I still have back problems from last year.


My last tip is related to hydration and food.

I don’t think there will be drink stations but there are fairly major river crossings at 11.5, 13.8, 16.8, and 36 kms. Depending on weather conditions, there could be small streams coming off the hills. I ran with 2L of water on my back which meant I did not have to faff at the rivers. Personal choice, I guess.

You need to be careful with food. The race is runnable compared to more normal hill races, so you will need to ensure you eat appropriately at the right times through the race. When I first ran, I completely forgot to eat anything until well past Luibeg (18kms) when I started feeling hungry. Too late. I then stuffed myself to catch up and my body spectacularly rejected the food from more than one orifice. So get the energy input right. You will need that energy for those last 16kms!

Anyway – Good luck to the Harriers running this year. It is an epic race but don’t underestimate it.


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4 comments on The Lairig Ghru Race – musings from someone who was beaten by this race – twice!

  1. Craig Weldon says:

    Thanks Rob. Considering this for this year – never been through the Lairig Ghru and the option of transport back to the start makes it very tempting!

  2. Mark Dawson says:

    Great report. I’d like to do this one day.

  3. gilly says:

    Some really good info there Rob, thank you. I camped at the Luibeg crossing last summer so watched various techniques of people crossing, some more successful than others!

  4. Dave Cairns says:

    Fantastic insight into the race Rob. Read and learn folks.

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