NUTS Karhunkierros Trail Ultra
NUTS Karhunkierros 83 km
Hautajärvi (Napapiiri) → Ruka (Kuusamo)
Race guide
Updated 28 July 2026
NUTS Karhunkierros 83 km starts at Hautajärvi on the Arctic Circle at 22:00 on Friday and finishes at Ruka. The measured course is 84.3 km with 1406 m of climbing, topping out at 491 m and dropping to 143 m. It follows the classic Karhunkierros trail — river gorges, suspension bridges, boardwalk and, at the end, the Konttainen and Valtavaara climbs. The late-night start means the first hours are run through the pale Kuusamo night: in late May at this latitude there is no true darkness, but a headlamp is still mandatory kit.
The course
From the Arctic Circle the trail drops into Oulanka National Park and follows the Oulanka river through canyon country. The first 27.6 km to the Oulanka visitor centre is the most runnable part of the race: wide trail, boardwalk and gentle gradients. From the visitor centre to Basecamp at 59.4 km the ground turns technical — roots, steps, suspension bridges and narrow canyon path. The final third from Basecamp over Konttainen (77.1 km) to the finish at 84.3 km holds the hardest climbing of the day, and it arrives with 60 km already in the legs.
Where the race is decided
1406 m of climbing over 84 km does not sound severe, but the profile is deceptive: the gain is split across hundreds of short pitches, and the closing Konttainen–Valtavaara section collects a large share of it. Two points decide the race. The first is the Oulanka cut-off, which forces a real pace from the gun. The second is the stretch after Basecamp, where the turn from night into morning, the drop in body temperature and the technical ground take more speed out of runners than the climbs do.
Pacing and fuelling
The aid stations are far apart: 27.6 km to Oulanka, 31.8 km on to Basecamp, 17.7 km to Konttainen and 7.2 km to the finish. The first two legs are both over 27 km, which in practice means three hours of self-sufficiency at a time. There is no water point at the start, so bottles must be filled before the gun. Plan carry capacity around those two long legs rather than around the average gap — that is the single most common planning error on this course.
Cut-offs and aid stations
The overall limit is 18 hours, so the finish closes at 16:00 on Saturday. There are two intermediate cut-offs: the Oulanka visitor centre at 5 hours (03:00 Saturday) and Konttainen at 15 hours (13:00 Saturday). The Oulanka cut-off is much tighter relative to distance — 27.6 km in five hours, at night, on technical trail, leaves little room for long stops. If the goal is simply to finish, that number is the one the whole plan should be built around. Runners in the 83 km have a drop bag carried from Ruka to the Oulanka visitor centre.
Weather and kit
Late May in Kuusamo can mean +20 °C or sleet. Low sections are usually wet with snowmelt, and the canyon trails along the Oulanka river stay slippery long after rain. Temperatures often fall close to freezing overnight, so a light wind shell and warm sleeves are not spare weight — they are what keeps the pace from collapsing in the small hours.
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Checkpoints & cut-offs
⚠ Auto-researched from public sources — aid stations and cut-offs may be incomplete. Confirm against the official roadbook before race day.
0 km · 237 m · —
27.6 km · 163 m · Sat 03:00
59.4 km · 235 m · —
77.1 km · 323 m · Sat 13:00
84.3 km · 358 m · Sat 16:00
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Course data researched from public sources — verify against the official roadbook.