Chichibu, Saitama Pref., Japan · Saturday, November 14, 2026

Fixed Distance 50K

FunTrails50K Round

27 days to go

50 km Distance

2,850 m Climbing

6.8 Grit · Hardcore

35.9915° N, 139.0858° E © OpenFreeMap © OpenMapTiles Data from OpenStreetMap

What the course asks

Climbing rate 57 m / km Mountain. Significant climbing. Steep sections will require power hiking.

Time limit 12 hours 14:24 min/km average. Comfortable. Room to walk the climbs and stop at aid. More forgiving than 73% of 50K races. Measured against 1058 races of the same distance. Cut-off calculator →

Field size ~622 Very large. Congested start, busy aid stations.

DUV results for the 2025 edition (50km) — 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 15°C

Night low 4°C

Rainfall Mostly dry

Daylight 10 h 19 m of light

Regional 2001-2020 average for November — NASA POWER, grid elevation 264 m. Not a forecast.

Results history

Year	Race	Finishers	Men's winner	Women's winner
2025	50km	622	Hajime Kasagi · 05:18:24	Yuri Yoshizumi · 06:06:10
2024	50km	518	Masatoshi Obara · 05:38:34	Yuri Yoshizumi · 06:18:44

The field grew 20% between 2024 (518) and 2025 (622). 15% of the 2025 field were women.

DUV results for the 2025 edition (50km) — 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.

Gear for this race

Chosen for 50 km of trail with 2,850 m of ascent.

Trail Running Shoes 57 m of climb per kilometre — grip and rock protection before cushioning.
Race Nutrition 50 km of self-supported fuelling between aid stations.
Hydration Vests Pole attachment and chest-strap stability on steep ground.
Trekking Poles 2,850 m of ascent to walk up.
Headlamps A 12 h limit puts you out there after dark.

New Balance

Fuel Cell Super Comp Trail

★★★★★ 4.5

Brooks

Catamount 3

RunRepeat found the Brooks Catamount 3 to have a cozier upper that enhances the overall fit, though breathability and durability could be better. iRunFar noted…

★★★★★ 4.5

Tailwind

Endurance Fuel

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

$25 ★★★★★ 4.8

Salomon

ADV Skin 12

Industry-standard 12L race vest with front flask pockets and minimal bounce.

$180 ★★★★★ 4.8

Komperdell

Carbon Ultralight Vario 4

4-section folding carbon poles with compact pack size for mandatory gear.

$160 ★★★★★ 4.5

Nitecore

UT32

Dual-beam trail running headlamp (1100 lumens) with spot and flood beams.

$100 ★★★★★ 4.5

All gear guides →

Overview

The FunTrails50K Round, organised by FunTrailRun, is a 50-kilometer trail race that will take place in Chichibu, Saitama Pref., Japan, on November 14, 2026. This race has been held 2 times before, with the first edition in 2024 and the latest in 2025.

With 2850 meters of elevation gain over 50 kilometers, this course has a climb-per-kilometer of 57 meters. The time limit is 12 hours, giving runners a cutoff pace of 14.4 minutes per kilometer. This cut-off is tighter than 27% of 50k cut-offs, but more generous than 73%.

The latest edition in 2025 saw 622 finishers. This makes the field bigger than 99% of 50k fields, and smaller than 1%.

Similar races

Other 50K trail ultras, closest in distance first.