Koshu, Yamanashi Pref., Japan · Sunday, November 8, 2026

Fixed Distance 100K

Koshu Alps Haute Route Challenge Klesa 108

20 days to go

108 km Distance

5,905 m Climbing

10.0 Grit · Elite / extreme

35.7044° N, 138.7294° E © OpenFreeMap © OpenMapTiles Data from OpenStreetMap

What the course asks

Climbing rate 55 m / km Mountain. Significant climbing. Steep sections will require power hiking.

Time limit 16 hours 8:53 min/km average. Firm. You are racing the clock from the start. Tighter than 73% of 100K races. Measured against 226 races of the same distance. Cut-off calculator →

Field size ~18 Tiny. You will run alone for most of it.

DUV results for the 2025 edition (108km) — finishers only. Starters are not published, so the field was at least this big and no finish rate can be given.

Typical conditions, November

Daytime high 13°C

Night low 3°C

Rainfall Mostly dry

Daylight 10 h 31 m of light

Regional 2001-2020 average for November — NASA POWER, grid elevation 732 m. Not a forecast.

Results history

Year	Race	Finishers	Men's winner	Women's winner
2025	108km	18	Ko Ito · 15:29:39	Sachi Nakano · 17:39:39

6% of the 2025 field were women.

DUV results for the 2025 edition (108km) — finishers only. Starters are not published, so the field was at least this big and no finish rate can be given.

Course notes

terrain This is a mountain course. Poles are highly recommended for the sustained climbs.
gear With trail terrain, choose a shoe with moderate cushioning for optimal performance.
nutrition For 100km+ efforts, prioritize real food at aid stations to prevent palate fatigue.

Gear for this race

Chosen for 108 km of trail with 5,905 m of ascent.

Trail Running Shoes 55 m of climb per kilometre — grip and rock protection before cushioning.
Race Nutrition Past 108 km the palate quits before the legs do — carry more than one flavour.
Hydration Vests Pole attachment and chest-strap stability on steep ground.
Trekking Poles 5,905 m of ascent to walk up.
Headlamps A 16 h limit puts you out there after dark.

Salomon

Prodigio Pro

RunRepeat found the La Sportiva Prodigio Pro to have a secure, locked-in fit due to its premium upper, and also praised the shoe's energetic ride, particularly…

$225 ★★★★★ 4.6

Tailwind

Endurance Fuel

All-in-one calorie and electrolyte drink mix. 200 calories per serving.

$25 ★★★★★ 4.8

Nathan

VaporKrar 12L

12L race vest co-designed with ultra champion Rob Krar, with insulated bladder pocket.

$170 ★★★★★ 4.6

LEKI

Ultratrail FX.One

Ultra-light carbon folding poles (135g each) designed for mountain ultra racing.

$200 ★★★★★ 4.6

Petzl

NAO RL

1500-lumen reactive lighting headlamp with 15-hour runtime. Automatic brightness adjustment.

$150 ★★★★★ 4.7

All gear guides →

Overview

The Koshu Alps Haute Route Challenge Klesa 108 is a 108km trail race with 5905m of elevation gain, held in Koshu, Yamanashi Pref., Japan. The course is scheduled to take place on November 8, 2026.

With 54.7 meters of climb per kilometer, this race is more challenging than 68% of 100k races. The 16-hour cut-off is tighter than 73% of 100k cut-offs, requiring a pace of 8.9 minutes per kilometer. The field of 18 finishers in 2025 was smaller than 68% of 100k fields.

Similar races

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