Ultra-Trail Kosciuszko by UTMB
Ultra-Trail Kosciuszko by UTMB – Kosci50
Perisher Ski Resort
Race guide
Updated 18 July 2026
The Kosci50 is the 50 km middle distance at Ultra-Trail Kosciuszko by UTMB, run from Perisher Ski Resort in the Snowy Mountains of New South Wales. With 1243 m of climbing and a high point of 2018 m, it packs the event's signature shape - alpine start, deep valley descent, and a hard climb back to the finish - into a single long day. What defines the Kosci50 is its late sting. After giving away nearly 600 m of height to the low point at Bullocks Flat, the course grinds back up to the Eagles Nest Waterpoint at 1920 m before dropping to the line. It is a race where the first half is genuinely fast and the last quarter decides your result.
The course: alpine start to a valley low and back up
From the start at 1720 m the route descends steadily to Bullocks Flat at 18 km, the low point of the course at 1133 m - almost 600 m of descent to open proceedings. This is the fast, flowing part of the day, and it sets a tempo that can be dangerously seductive if you let your quads absorb the whole drop. From Bullocks Flat the profile turns upward. The course climbs to Ngarigo Campground at 25.7 km (1229 m), continues to Village Green at 37.2 km (1370 m), then delivers its defining feature: the pull up to the Eagles Nest Waterpoint at 47.4 km (1920 m). A short descent brings you to the finish at 1370 m by 50 km. The high point of 2018 m is reached on that final climb, making the closing 13 km the highest and hardest of the whole race.
Where the race is won or lost: Village Green to Eagles Nest
The decisive section is the climb from Village Green (1370 m at 37.2 km) to the Eagles Nest Waterpoint (1920 m at 47.4 km) - around 550 m of ascent in the final ten kilometres, topping out at 2018 m before the drop to the finish. Coming this late, after a big early descent and a long valley re-ascent, it is where under-fuelled or over-eager runners come undone and where disciplined ones make up ground. The strategic pairing is the opening descent to Bullocks Flat and this closing climb. Every extra minute of braking damage you take dropping to 1133 m in the first 18 km is paid back with interest on the Eagles Nest grind. Treat Village Green as the launch pad for your real race: it is a crew point and your last full checkpoint, because Eagles Nest at 47.4 km is water only. Leave Village Green with calories and layers sorted for the exposed high-country finish.
Pacing and fuelling to the cut-offs
The Kosci50 cut-offs are: Bullocks Flat Thursday 11:45 (18 km), Ngarigo Campground Thursday 13:45 (25.7 km), Village Green Thursday 16:45 (37.2 km) and the finish Thursday 21:15. The schedule leaves the most time for the final segment, which is appropriate given the Eagles Nest climb is the toughest part - but do not squander that buffer early. Aim to reach Village Green well inside 16:45 so you can climb the last 13 km without racing the clock in the dark. On supplies, mind the spacing at both ends. The opening 18 km to Bullocks Flat is a single long descent with no checkpoint, so carry enough fluid and food to cover it. Then load up at Village Green for the climb home, since the only support between there and the finish is water at Eagles Nest. Solid calories before that 550 m ascent will do more for your finish time than any pace you hold on the early downhill.
Conditions to expect
This is an alpine race that both starts and finishes high. The opening kilometres sit above 1700 m and the closing climb reaches 2018 m at Eagles Nest, so you are exposed to fast-changing Snowy Mountains weather at the two ends of the course while the valley around Bullocks Flat offers more shelter. Expect a real swing between the runnable, warmer valley section and the cold, windy tops. With a Thursday 21:15 finish cut-off, the tail of the field will be climbing to Eagles Nest and descending to the line toward dusk, so a headlamp and genuine warm, windproof and waterproof layers are worth carrying even if the day starts mild. Run the first descent within yourself, arrive at Village Green with time and calories in hand, and save your legs for the highest, most exposed stretch of the day right at the end.
Race Ultra-Trail Kosciuszko by UTMB – Kosci50 with Crux
Get the strategy, fuelling and crew plan dialled for this exact course — built from the real route, climbs and cut-offs. Your first race is free.
Plan this race — freeCourse profile
Checkpoints & cut-offs
✓ Course data verified against the official source (2026-07-17) · official source
0 km · 1720 m · —
18 km · 1133 m · Thu 11:45
25.7 km · 1229 m · Thu 13:45
37.2 km · 1370 m · Thu 16:45
47.4 km · 1920 m · —
50 km · 1370 m · Thu 21:15
More races
More UTMB World Series
More in Australia
Similar distance (50–100 km)
Racing Ultra-Trail Kosciuszko by UTMB – Kosci50?
Get a complete race strategy — pacing, fuelling, crew plan and the crux moments — built on this exact course.
Plan your race in Crux →Strava is your training. Crux is your races.