Ultra-Trail Kosciuszko by UTMB
Ultra-Trail Kosciuszko by UTMB – Kosci100
Perisher Ski Resort
Race guide
Updated 18 July 2026
The Kosci100 is the 106 km flagship of Ultra-Trail Kosciuszko by UTMB, run out of Perisher Ski Resort high in New South Wales' Snowy Mountains. With 2814 m of climbing and a high point of 2221 m, it is one of the few genuinely alpine hundreds on the Australian calendar: the entire first half sits above 1600 m before the course plunges toward the valley and then claws its way back up to finish. What defines this race is not a single monster climb but a long high-country traverse followed by a brutal sting in the tail. The lowest point, Bullocks Flat at 1131 m, comes at 75.2 km, which means the closing quarter of the race is net uphill on tired legs. Runners who bank the runnable early kilometres sensibly and save something for the Eagles Nest climb are the ones who finish inside the Saturday 12:00 cut-off.
The course: a high-country loop from Perisher
The route starts at 1720 m and stays up on the tops for a long time. From the start it rolls to Charlotte Pass Resort at 16.3 km (1756 m), then out to Charlotte Pass Lookout at 40.4 km (1830 m) - the highest checkpoint area of the day, with the course topping out at 2221 m along the way. From there it drops to Guthega Base Camp at 50.3 km (1629 m) and swings back to Perisher Ski Tube at 62.5 km (1723 m). The character then changes completely. After Perisher the trail descends hard to Bullocks Flat at 75.2 km, the low point at 1131 m, before working back up through Ngarigo Campground (82.8 km, 1229 m) and Village Green (94.2 km, 1370 m). The final signature is the climb to Eagles Nest Waterpoint at 104.3 km (1920 m) followed by a short drop to the finish at 1370 m. It is a course of two clear halves: exposed alpine tops first, a deep descent and a stinging re-ascent second.
Where the race is won or lost: the Eagles Nest climb
On paper the biggest single loss of height is the descent from Perisher Ski Tube (1723 m at 62.5 km) down to Bullocks Flat (1131 m at 75.2 km) - close to 600 m of downhill that hammers quads already 75 km deep. Manage that descent poorly and the closing climbs become damage control rather than racing. The decisive effort is the run home from Village Green. From 1370 m at 94.2 km the course grinds up to the Eagles Nest Waterpoint at 1920 m by 104.3 km - roughly 550 m of gain in about ten kilometres, right at the end, above the treeline. This is where places change hands and where under-fuelled runners walk it in. Treat Village Green as the real start of your race: leave with your headlamp, layers and calories sorted, because Eagles Nest is a waterpoint only and there is nothing to hide behind up there before the final drop to the line.
Pacing and fuelling to the cut-offs
The cut-offs tighten as the day goes on. Early checkpoints are relatively generous - Charlotte Pass Resort closes Friday 12:10 at 16.3 km and Charlotte Pass Lookout Friday 18:10 at 40.4 km - but the back half compresses: Bullocks Flat Saturday 03:05 (75.2 km), Village Green Saturday 08:00 (94.2 km) and the finish Saturday 12:00. The gap from Village Green to the line spans the hardest climb of the race with the least time buffer, so build your plan backwards from an 08:00 arrival at Village Green with time in hand. Watch the aid spacing when you carry food and fluid. The longest dry stretch is the 24 km between Charlotte Pass Resort (16.3 km) and Charlotte Pass Lookout (40.4 km) high on the tops - carry enough for two-plus hours of alpine effort there. Later, plan to leave Village Green fully stocked because Eagles Nest at 104.3 km is water only; you want solid calories on board for that 550 m climb rather than expecting a full aid station near the top.
Conditions to expect
This is high alpine terrain by Australian standards, with the bulk of the first 60 km above 1600 m and a high point of 2221 m. Weather in the Kosciuszko high country turns fast and is fully exposed above the treeline - the traverse between Charlotte Pass and Guthega, and the final push to the 1920 m Eagles Nest, offer little shelter from wind, cold or sun. Come prepared for a large temperature swing between the daytime tops and the overnight low around Bullocks Flat. Because the race runs into the night and finishes Saturday midday, most runners spend the deep descent to Bullocks Flat and the climbs through Ngarigo and Village Green in darkness. A reliable headlamp with spare batteries, genuine warm and waterproof layers for the exposed sections, and a disciplined approach to the long high-country carries are the practical essentials. Respect the tops early, save your quads on the big Perisher descent, and keep enough in the tank for the Eagles Nest sting.
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Checkpoints & cut-offs
✓ Course data verified against the official source (2026-07-17) · official source
0 km · 1720 m · —
16.3 km · 1756 m · Fri 12:10
40.4 km · 1830 m · Fri 18:10
50.3 km · 1629 m · Fri 20:40
62.5 km · 1723 m · Sat 00:00
75.2 km · 1131 m · Sat 03:05
82.8 km · 1229 m · Sat 05:15
94.2 km · 1370 m · Sat 08:00
104.3 km · 1920 m · —
106 km · 1370 m · Sat 12:00
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