Trail Running > Routes > Brecon Beacons Routes > Pen y Fan Horsehoe
A 20 km “snakes and ladders” tour of spectacular Brecon Beacons peaks including Pen y Fan — the highest point in South Wales.
Why run this trail?
More than 250,000 people a year scale Pen y Fan – the highest point in the Brecon Beacons at 886 metres – and its neighbouring peaks of Corn Du and Cribyn. As you’d expect, the tracks are well defined, built like sandstone motorways and inevitably busy on a fine day. But the crowds don’t detract from the views and this route rewards you with spectacular panoramas wherever you pause to catch your breath.
I did the ‘extended’ horseshoe route – an ascent to the ridge of Graig Fan Ddu from Taf Fechan Forest followed by a scalloped, clockwise loop across ridges and summits. It’s a bit of a staple and I met plenty of other runners and walkers tackling the same route – or slight variations – in both directions.
Right up to the 11th hour I debated: should I ascend via Cefn Cwm Llwch (28 km) or from Talybont Reservoir (32 km)? There’s no shortage of options for a longer run here.
After snatching just five hours sleep the night before, I was thankful I had settled on a shorter option from Taf Fechan. As it happened, this run was much tougher than I expected, with no respite from hard running surfaces – be that the tightly packed sandstone pathways or the baked earth offered up after a long hot summer. I was yearning for wet feet and a bit of good old fashioned mud by the time this run was over.
Graig Fan Ddu and Corn Du
I set off from the car park at Taf Fechan at 10 am on a beautiful July morning. The valley was still, the temperatures already in the low 20s. The first climb began promptly after crossing the Neuadd Dam – a sharp punt up to the ridge of Graig Fan Ddu, turning steep and rocky near the top.
A quick detour south to the war memorial trig point didn’t last long as I was accosted by wasps and opted for a 50 m dash to shake them off. Back on track, it was simply a case of following the obvious ridgeline north as views of the glacial bowl and distinctive summits opened out around me.
This first section is a fairly undemanding 3.5 km of sightseeing across gently undulating terrain. The track offers plenty of lines to pick from and great views as it skirts the precipice. So iconic are the peaks of Corn Du, Pen y Fan and Cribyn that I found it hard to peel my eyes away from them as they inched gradually nearer.
Dropping to Bwlch Duwynt, the foot traffic noticeably swelled as paths converged from the popular approach routes. A short, stiff jog and scramble later, I was on the craggy top of Corn Du (873 m), with expansive views over Cwm Llwch and the town of Brecon to the north.
Pen y Fan: The Summit Circus
From Corn Du, the 500 m hop to Pen y Fan is foolproof – just follow the train of people headed to the summit!
Two things grabbed my attention once I got there:
1) About 30 very sturdy fellows in matching t-shirts were erecting scaffolding right by the summit cairn. A fundraising event, it turned out: they had carried every pole up from the valley. Possibly the next big thing in wacky outdoor pursuits. Gentlemen, I think you’re on to something…
2) The incredible views from the summit – particularly the eastern ledge, which showcases the peaks of Cribyn, Fan y Big and Waun Rydd as they snake away into the haze like breaking surf.
Cribyn and Fan y Big
It’s a steep and rocky descent on a hard packed trail from the summit of Pen y Fan en route to Cribyn (795 m) – an angular wedge of green felt that gets more imposing the closer you get. At this point, my feet were glad of the large, solitary pool of lukewarm water at the base of the climb.
There are very few switchback tracks in this series of peaks – the local way-marking forefathers must have been fairly direct in their philosophy. Cribyn is no exception. About half way up the climb, my head dropping and hands planted firmly on knees, I admitted defeat and switched to a brisk hike. The reward? Spotting the smallest lizard I have ever seen, who obliged me with a photograph.
The crowds thinned on the climb up to Cribyn and the track grew less regimented. The summit offered great views back to Pen y Fan – a classic ‘crest of the wave’ view of this prominent mountain.
A fast, winding descent from Cribyn offered the welcome option of swapping rocky single track for patches of grass as the final summit of the day – Fan y Big – loomed into view ahead. The peak features distinctive tiers of rock banding the face of the mountain which are typical of the area.
The climb to Fan y Big (719 m) is similar in length and gradient to Cribyn, but gifted with a few switchbacks from about the half-way point. The summit offered a cracking panorama of the entire ridge I had traversed. Naturally I just had to grab someone to take my photo on the famous ‘diving board’ rock which juts out over the cliff edge. Shamelessly filed under mandatory clichés.
The Long Road Home
Shaking out tired legs and munching an energy bar, I struck out along a sandy single track through the heather towards Waun Rydd. From this point, my route then took me south on easy trails, tracing the Fan Las and Fan Ddu ridges before finally dropping quickly down through the bracken and trees to Blaen y Glyn Isaf Car Park.
Distracted by a glimpse of the steam railway at Torpantau, I missed my turning for the short homeward section through Taf Fechan Forest. This provided an unwelcome sting in the tail – an additional 2 km of hot, thankless tarmac to reach my car.
Not the ending I’d hoped for, but it didn’t dent the satisfaction of a superb morning in the mountains. Mission accomplished, it was tally-ho to my digs in Talybont for a spot of lunch and a gigantic ginger beer by the canal.
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All routes and GPX files are provided as a guide only. Conditions, rights of way, and landmarks may change. Always carry an up‑to‑date map and use your own judgement. See the Trail Run Disclaimer page for details.