Yubetsu, Japan · Sunday, June 28, 2026

Fixed Distance 100K

Lake Saroma 100 Km Ultramarathon

Race completed
100 km Distance
not publishedn/a Climbing
5.0 est Grit · Challenging

Calculated from 100 km alone — the organiser has not published an elevation profile. Read 5.0 as a floor, not a verdict.

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44.1515° N, 143.5730° E© OpenFreeMap © OpenMapTiles Data from OpenStreetMap

What the course asks

Time limit 13 hours 7:48 min/km average. Firm. Sustained running. Long aid-station stops will cost you. Climbing is unpublished, so this pace is a ceiling on the effort, not a measure of it. Tighter than 88% of 100K races. Measured against 208 races of the same distance. Cut-off calculator →
Field size ~2,632 Very large. Congested start, busy aid stations.

DUV results for the 2026 edition (100km) — finishers only. Starters are not published, so the field was at least this big and no finish rate can be given.

Typical conditions, June

Daytime high 19°C
Night low 10°C
Rainfall Mostly dry
Daylight 15 h 29 m of light

Regional 2001-2020 average for June — NASA POWER, grid elevation 190 m. Not a forecast.

The Aid Station

Course-specific beta from the community

👟 gear

With road terrain, choose a shoe with moderate cushioning for optimal performance.

By UltraHub Expert
🥤 nutrition

For 100km+ efforts, prioritize real food at aid stations to prevent palate fatigue.

By UltraHub Expert

Gear for this race

Chosen for 100 km of road.

  • Trail Running Shoes100 km of road — cushioning that is still there in the last quarter.
  • Race NutritionPast 100 km the palate quits before the legs do — carry more than one flavour.
  • Hydration VestsFlask capacity for 100 km, without the bounce.
  • HeadlampsA 13 h limit puts you out there after dark.
  • AccessoriesChafe and blisters end more 100 km races than fitness does.

Salomon

Aero Glide 4 Grvl

$159.95 ★★★★★ 4.5

Hoka

Challenger 7

★★★★☆ 4.3

Tailwind

Endurance Fuel

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

$25 ★★★★★ 4.8

Naked

Running Band

Minimalist waist-mounted running band. Ultra-light alternative to a vest for shorter races.

$60 ★★★★☆ 4.3

Nitecore

UT32

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

$100 ★★★★★ 4.5

Squirrel's Nut Butter

Anti-Chafe Balm

All-natural anti-chafe balm. Essential for 100+ mile races.

$12 ★★★★★ 4.8
All gear guides →

Course Notes

Eine große Runde um den Saroma See mit über 2000 Teilnehmern.

Similar races

Other 100K road ultras, closest in distance first.