Canfranc-Canfranc
Canfranc-Canfranc Ultra 100K
Canfranc-Estación
Race guide
Updated 19 July 2026
The Canfranc-Canfranc Ultra 100K is a savage Pyrenean loop starting and finishing at the iconic Canfranc-Estación, one of the most architecturally striking railway stations in Europe. With 100 km of distance and 8617 m of positive elevation gain — peaking at 2865 m — this is not a race that lets you coast. The course circles through some of the most remote and spectacular terrain in the Spanish Pyrenees, passing through the Collarada massif, the ski resorts of Candanchú and Astún, and the high ridges above Formigal before dropping back to the valley floor. The sheer density of climbing — averaging over 86 m of gain per kilometre — means every sector demands respect. This is a race that rewards mountain experience, careful pacing and honest preparation.
Course & Terrain Overview
The route is a genuine mountain loop that never strays far from serious altitude. From Canfranc-Estación (1198 m) the course climbs immediately, reaching the Ibón de Ip sector at 16 km after dropping to 1060 m — a deceptive early dip that signals the undulating nature of the opening stretch. The most committing section follows: the Collarada sector between kilometres 16 and 49 takes runners into genuinely remote terrain, cresting around 2505 m at the 30 km checkpoint, with the high point of the entire course at 2865 m somewhere in this block. This is the longest stretch between crew access points and the most exposed part of the race. The mid-race return to Canfranc-Estación at 50 km gives runners a chance to regroup before the second half pushes west through Candanchú (63 km, 1479 m) and back up to Astún (72 km, 2141 m), before the Formigal sector at 84 km rounds out the climbing. Trails vary from rocky high-mountain paths and ridge lines to forest tracks and ski-area service roads — expect mixed underfoot conditions throughout.
The Decisive Climbs and Where the Race Is Won or Lost
The Collarada sector is where races unravel. Spanning kilometres 16 to 49, it represents over 30 km of high-altitude, remote terrain with the course hitting its ceiling of 2865 m somewhere within it. There is no crew access between the start and the 30 km Collarada checkpoint, and then again none until the mid-race pass at 50 km — meaning runners carry everything they need through the most technical and exposed section of the course. Blowing up here, even slightly, leaves you depleted with 50 km still to run. The second decisive test comes in the Astún climb: after what might feel like a recovery leg through Candanchú, the course rises again to 2141 m at 72 km, loading tired legs with serious vertical at a point when glycogen stores are critically low. The Formigal sector at 84 km is the last major elevation block before the final descent to Canfranc-Estación. Runners who arrive at Formigal in control tend to finish; those who have overcooled on the descents or under-fuelled through Astún often face a painful final 16 km.
Pacing & Fuelling Strategy
With 8617 m of climbing packed into 100 km, pace must be built around vertical rather than distance. The opening 16 km to Ibón de Ip feel accessible but mask the brutal Collarada bloc that follows — resist the urge to race early. Power-hike the steeper ascents from the gun and preserve your quads for the second half. The crew point at Canfranc-Estación (50 km) is your most important logistical moment: use it to fully resupply calories and fluids, change socks and shoes if needed, and do an honest check on your condition before committing to the second 50 km. Fuel early and often — the remote Collarada section between 16 and 50 km has only one checkpoint (30 km), so carry enough calories to cover at least 3–4 hours of hard mountain effort without external support. Electrolytes matter in the heat of a summer Pyrenean day; the altitude and exposure also mean sweat rates can deceive. Use Candanchú (63 km) and Astún (72 km) checkpoints aggressively — eat real food if your stomach allows and top up every fluid reservoir. The finish cut-off is Sunday 13:00 at Canfranc-Estación, so anyone slipping behind target pace through the Formigal sector needs to move with purpose on the final descent.
Conditions to Expect
The Pyrenees above 2000 m can serve almost any weather even in summer race conditions. The Collarada massif and the high ridges above Astún are fully exposed to wind and rapidly changing weather — afternoon thunderstorms are a genuine risk in the mountain environment, and temperatures at 2865 m can drop sharply even after a warm morning in the valley. Carry a mandatory shell layer and be prepared to use it. Snow patches may persist in the Collarada sector into early summer depending on the year. Conversely, on clear days the sun at altitude is fierce and UV exposure is significant — sunscreen and eye protection are not optional. The lower trail sections, particularly around Candanchú and the valley approaches, can be muddy after rain, making traction a factor. Plan for at least one major weather change during the race and pack accordingly in your drop bags at the crew-access checkpoints.
Key Checkpoints & Logistics
Canfranc-Estación serves as start, mid-race pit stop and finish, making it the logistical hub of the entire event. Crew can access runners here at 0 km, 50 km and 100 km — three genuinely useful interventions that should be planned in detail in advance. Drop bags or crew support at Candanchú (63 km) round out the accessible points. Astún (72 km) and Formigal (84 km) are checkpoints but the data indicates crew access specifically at Candanchú, so confirm crew arrangements with race organisation. The Ibón de Ip sector at 16 km and the Collarada checkpoint at 30 km are remote — no crew access — so treat them as resupply stations only and brief your support team accordingly. With a Sunday 13:00 finish cut-off, calculate your expected finish time against your realistic mountain pace: 8617 m of climbing on 100 km demands conservative arithmetic, and many runners underestimate the cumulative fatigue of the second half when planning splits.
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Checkpoints & cut-offs
✓ Course data verified against the official source (2026-07-05) · official source
0 km · 1198 m · Fri 22:00
16.6 km · 1068 m · Sat 02:30
27.8 km · 2230 m · —
32.5 km · 2111 m · —
42.3 km · 1742 m · Sat 14:30
50.5 km · 1806 m · Sat 17:30
62 km · 1400 m · Sat 22:00
72.1 km · 2127 m · Sun 02:00
82.4 km · 1592 m · Sun 05:00
91.3 km · 1875 m · —
101 km · 1198 m · Sun 13:00
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