Name: Shimanto River Ultra Marathon Online Challenge 【2 Month 100km Stage 1】 (四万十川ウルトラマラソン オンラインチャレンジ【２month 100km Stage 1】)
Start: 2026-09-01
End: 2026-09-01

About the Event

Immerse yourself in the serene beauty of Japan's last clear river, the Shimanto River, as you take on the challenge of the Shimanto Ultra Marathon. Whether you are an experienced ultramarathon runner or someone who dreams of one day conquering this legendary course, your presence is warmly welcomed.
The event offers a range of participation options to suit every budget and preference:
- For those looking for basic recognition, a T-shirt can be purchased separately at 4,990 yen.
- Participants opting for the next level receive either Shimanto udon or a long-sleeve T-shirt with their registration fee set at 6,990 yen.
- A more premium option includes a grilled horse mackerel skewer, cap, pants, or pullover hoodie priced at 8,990 yen.
- The top-tier package costs 12,990 yen and provides either Shimanto beef (for sukiyaki or yakiniku) or eels from the Shimanto region. This option also comes with a set of original wear including a cap, long-sleeve T-shirt, pants, and pullover hoodie.
The Shimanto Ultra Marathon is not just about running; it’s an experience that connects you to the stunning natural landscape along the Shimanto River. As you traverse through picturesque countryside dotted with rice paddies and traditional Japanese villages, each step brings a deeper appreciation for this unique environment. The race route winds its way past historic sites and local landmarks, offering runners a rich tapestry of cultural and scenic highlights.
The event is designed to cater to all levels of endurance athletes who wish to test their limits while enjoying the tranquility and beauty that Shimanto has to offer.

Races Offered

November Run 1month 100km

Sep 01, 2026

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Distance — 100K

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Type — Running

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21 days remaining

October Run 1month 100km

Sep 01, 2026

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Distance — 100K

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Training 1month 100km

Sep 01, 2026

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Distance — 100K

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Type — Running

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Year-end 1month 100km

Sep 01, 2026

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Distance — 100K

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２month 100km Stage 1

Sep 01, 2026

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Distance — 100K

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Type — Running

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２month 100km Stage 2

Sep 01, 2026

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Distance — 100K

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Type — Running

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３month 100km

Sep 01, 2026

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Distance — 100K

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Type — Running

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21 days remaining

Weather History

These values represent the 3-year monthly averages for September in .

thermostat Temperature

16.7° / 23.6°

wb_sunny Feels like

17.9° / 25.0°

light_mode Avg sunshine hours

8h 44m

water_drop Avg rainfall

5.7 mm

ac_unit Avg snowfall

—

air Avg wind speed

4.7 km/h (Light breeze)

opacity Sweat loss rate

High

terrain Course conditions

Hard and dry surface

sunny Max UV Index

Moderate (5.0)

humidity_mid Humidity

86.6%

wb_twilight Sunrise

05:25

nightlight Sunset

17:50

Hotels & Places to Stay

Runner Reviews

Read what other athletes have to say about their experience at the Shimanto River Ultra Marathon Online Challenge 【2 Month 100km Stage 1】 (四万十川ウルトラマラソンオンラインチャレンジ【２month 100km Stage 1】).

★ ★ ★ ★ ★