Ultra-Trail Snowdonia by UTMB®
Ultra-Trail Snowdonia by UTMB® – UTS 80K
Caernarfon → Llanberis
Race guide
Updated 18 July 2026
The UTS 80K is the middle distance of Ultra-Trail Snowdonia by UTMB, a 78 km point-to-point through the mountains of North Wales that starts at sea level in Caernarfon and finishes in Llanberis. With 2,361 m of vertical gain and a high point of 991 m, it packs a lot of climbing into a comparatively short distance, and the numbers only hint at how relentless the terrain underfoot really is. This is a race defined by contrast: it opens on lanes and lower ground barely above the tide line, then hauls you up into the high, rocky heart of the Snowdon massif before dropping you back to the finish. Six checkpoints break the route into manageable chunks, and a tight cut-off schedule means you are effectively racing the clock from the first climb onward.
The Course: Caernarfon to Llanberis
The UTS 80K runs 78 km from Caernarfon on the coast to Llanberis at the foot of the Snowdon range. The start line sits at just 6 m of elevation, so the entire climb of the day is still ahead of you when the gun goes. From Caernarfon the route works inland and upward to the first checkpoint at Y Fron (16.7 km, 284 m), the first real taste of the gradient this course trades in. After Y Fron the terrain steepens and turns genuinely mountainous. The route crosses the flank of the Snowdon massif, passing the checkpoint named Llanberis Path (31.3 km, 200 m) before pushing on toward the course's 991 m high point in the high ground of the range. It is a lumpy, uneven profile rather than one long climb: checkpoint elevations swing from Gwastadannas at 91 m up and back down to Beddgelert at just 46 m, so you are constantly gaining and giving back height across the 78 km.
Where the Race Is Won and Lost
The decisive terrain is the central stretch between Y Fron (16.7 km, 284 m) and Gwastadannas (45 km, 91 m). This is where the course climbs to its 991 m high point and where the ground is at its most technical and exposed. Getting over the top and down to Gwastadannas with your legs intact is the whole game, because the descents here are as punishing as the climbs and can wreck quads that still have a marathon of running left in them. From Gwastadannas the route plunges to Beddgelert (59.1 km, 46 m), the lowest of the late checkpoints, before stinging you with a final climb to Rhyd Ddu (67.5 km, 185 m) and the last drop into Llanberis (78 km, 105 m). That closing sequence, a big descent followed by one more climb on tired legs, is where positions change hands. Runners who overspend on the high central section pay for it on the Rhyd Ddu climb.
Pacing and Fuelling Around the Cut-Offs
The cut-off schedule is unforgiving and should shape your entire plan. Y Fron closes Friday at 23:00, Llanberis Path at 02:00 Saturday, Gwastadannas at 05:00, Beddgelert at 08:00, Rhyd Ddu at 10:00 and the finish at Llanberis at 12:00. That structure tells you this is largely a night race through the mountains, so a reliable headtorch (and spare) and the discipline to move steadily in the dark are non-negotiable. Aid-station spacing is manageable but the sections are slow: 16.7 km to Y Fron, then roughly 14 km legs to Llanberis Path and Gwastadannas across the hardest ground. Carry enough food and fluid to cover four-plus hours between resupply on the central climbs, because your pace there will be far slower than the distance suggests. Beddgelert at 59.1 km is the sole crew point, making it the natural place to reset, restock and steel yourself for the Rhyd Ddu climb and final descent.
Conditions to Expect
Snowdonia's high ground reaches 991 m on this course and the weather there can be a different world from the mild coast at Caernarfon. Even in the race season, the exposed sections near the high point can serve up wind, driving rain, low cloud and a sharp drop in temperature, and because much of the route is run through the night the cold bites harder. Layer for the summits, not for the start line at 6 m. Underfoot the mountains of North Wales are rocky, rough and frequently wet, with loose stone and slick rock that demand full attention on both climbs and descents. This is not a course for fast, flowing running; it rewards sure footing, good grip and patience. Plan your times conservatively, respect how much the technical ground and darkness will slow you, and treat every cut-off as a checkpoint you want to reach with a comfortable buffer rather than a photo finish.
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Checkpoints & cut-offs
✓ Course data verified against the official source (2026-07-17) · official source
0 km · 6 m · —
16.7 km · 284 m · Fri 23:00
31.3 km · 200 m · Sat 02:00
45 km · 91 m · Sat 05:00
59.1 km · 46 m · Sat 08:00
67.5 km · 185 m · Sat 10:00
78 km · 105 m · Sat 12:00
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