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Okushinano 100K

Basic Listing
  1. Okushinano100 Race Committee
  2. 2026 Edition

Three loops through mountains, ancient beech forests, and orchard country of Northern Nagano

Directions
This event took place on June 06, 2026

Nearby races

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All trail races in Japan→
June 06, 2026
Saturday 5:00am GMT+9 start
Kijimadaira, Nagano
Japan
100 km
Loop Course
4,800 m
Elevation Gain
Historical weather
53°F / 69°FLo/Hi Temp
51°F / 70°FFeels Like
76%Cloud Cover
0% (0.18 in)Precipitation
8 mphWind Speed
76%Humidity
4:27 AMSunrise
7:02 PMSunset
Open Registration
No lottery
No Service Requirement
Does not require trail or volunteer work
No Qualifier
No qualifier race required
Very Challenging
Experienced ultrarunners
Links
WebsiteInstagramFacebook
2021
Established
700
Field Size
73%
Finish Rate

What Makes It Great

A 100km loop through three distinct landscapes of Northern Nagano's Oku-Shinano region: the mountains surrounding solitary Mt. Kosha, primeval beech forests with trees over 300 years old, and the rural orchards and pastoral countryside of Kijimadaira Village. Runners traverse centuries-old mountain trails connecting remote hamlets, stream-fed valleys, and agricultural land still bearing the character of Japan's heavy-snowfall interior. The course combines technical mountain terrain with scenic village running, starting and finishing at the Cupid of Romance Snow Resort. Bear bells are mandatory gear, reflecting the wild nature of the course. A Western States 100 2027 qualifying race carrying 4 ITRA points.

Difficulty

Advanced
7/10

Experienced ultrarunners

Steep Climbing
Technical Descent
Technical Terrain
Night Running
Variable Weather
Strict Cutoffs

Race Highlights

Western States 2027 qualifier
Finishing the 100km earns a qualifying ticket for the Western States 100-Mile 2027 lottery, plus 4 ITRA points
300-year-old primeval beech forests
Course loops through ancient beech forests that have survived centuries of heavy snowfall in Japan's interior highlands
Three distinct loop sections
Unique triple-loop design takes runners through alpine mountain terrain, ancient beech forest, and rural orchards/pastoral countryside
4,800m elevation gain
Significant mountain climbing through the ranges surrounding Mt. Kosha with 7 mandatory cutoff checkpoints
98 minutes from Tokyo
Hokuriku Shinkansen from Tokyo to Iiyama makes this one of Japan's most accessible mountain ultras — no domestic flight needed

Okushinano 100K

Kijimadaira, Nagano, JapanJune 06, 2026

June 06, 2026
Course map for Okushinano 100K
DistDistance100 km
GainElevation Gain4,800 m
LimitCutoff21 h
Steep ClimbingTechnical DescentNight RunningVariable WeatherStrict Cutoffs

Entry Timeline

Race DayJune 06, 2026

Lottery

This event uses open registration - no lottery entry required.

Qualifier

This event does not require a qualifier for entry.

Service Requirement

This race does not have a service requirement for entry.
100.0 km
Distance
Loop
Route
21h
Cutoff Time
914 m
Average Elevation
4,800 m
Total Ascent
4,551 m
Total Descent
1,709 m
High Point
377 m
Low Point
Course map
Launch Course Explorer

Aid Stations

LocationkmElevation
Start
Start
0.0605 m
Donguri Park
Aid Station
13.0756 m
Venue
Aid Station
27.0605 m
Kayanodaira Water Aid
Aid Station
38.01,350 m
Kayanodaira 1
Aid Station
48.01,535 m
Kayanodaira 2
Aid Station
58.01,535 m
Nukasen 1
Aid Station
72.0739 m
Keyakinomori Park
Aid Station
84.0472 m
Nukasen 2
Aid Station
95.0739 m
Finish
Finish
100.0604 m

Sign in to see cutoffs, crew access, drop bags, and services for every aid station.

No on-site camping available

Crew Access Points

Pacer Rules

  • One pacer allowed per runner starting from the 27km point (Aid Station A2 at the Cupid of Romance Snow Resort). Pacers must use the designated Pacer Access Bus to reach assigned meeting points at A2 (27km), A4/A5 (38/48km at Kayanodaira), or A6 (72km at Nukasen).
  • Pacers may not carry a runner's gear or provide any physical assistance such as pushing or pulling. Support crews may not use the Pacer Access Bus.

Crew Rules

  • Crew and spectator access permitted at the start/finish venue (Cupid of Romance Snow Resort), and at Donguri, Kayanodaira, and Keyakinomori park aid stations.
  • No crew or spectator access at Nukasen Aid Station — no parking lot is available.
  • Private crew support in the Kayanodaira area requires payment of a 500 yen/day access fee to the Kayanodaira Information Center.
Daylight
14h 35m
4:27 AM7:02 PM
69°F / 53°F
Feels like 70°F / 51°F
Temperature Hi/Lo
0% (0.18 in)
Precipitation
8 mph
Wind
76%
Humidity
76%
Cloud Cover
Based on historical averages for June 06
Rapid Weather Changes

June mountain weather in Northern Nagano can bring sudden rain and rapidly changing conditions. Rain gear is mandatory.

Cold/Hypothermia Risk

Night temperatures drop significantly at elevation. The 5am start means runners will finish in pre-dawn hours (up to 2am).

Wildlife

Black bears are present throughout the course area. A bear bell is mandatory gear for all 100km and 50km runners.

Gear Rules

Trekking poles allowed

Required Gear

  • Mobile phone (Must be the number registered at time of entry)
  • Portable cup
  • Water (1 liter or more) (Plus sufficient food for each runner)
  • Survival blanket (At least 130cm × 200cm)
  • Taping tape
  • Course map (Download from event website or use smartphone/watch with GPX uploaded)
  • Rain jacket with hood (Waterproof/breathable material (GORE-TEX or equivalent) with seam-taped seams)
  • First aid kit (Bandage, antiseptic, etc.)
  • Headlamp (With spare batteries (additional lights may substitute for spare batteries))
  • Bear bell (Required due to bear presence in course area)

Recommended Gear

  • Rain pants
  • Trekking poles (Prohibited in Kayanodaira area (48km–58km section))
  • Gloves
  • Flashing or reflector light (To be visible to vehicles when running at night)
  • Venom extractor (poison remover)

Featured Videos

奥信濃100 2025 公式ハイライト (2025 Official Highlights)
奥信濃100 2025 公式ハイライト (2025 Official Highlights)
ALP SKI TEAM•2025
2024 奥信濃100 ハイライト動画 (2024 Highlight Video)
2024 奥信濃100 ハイライト動画 (2024 Highlight Video)
ALP SKI TEAM•2024
【奥信濃100】Seeking Blossoms — Runner's Perspective 100km
【奥信濃100】Seeking Blossoms — Runner's Perspective 100km
Sakura Inoue (井上 咲楽)•2024

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