12th Yodogawa

Eco Marathon

scroll for race details

November 21, 2021

Yodogawa (Osaka)

10km, 21.1km

10th Nikotama

Eco Marathon

scroll for race details

September 12, 2021

Tama River (Tokyo)

10km, ekiden

10th Nikotama

Eco Marathon

scroll for race details

September 12, 2021

Tama River (Tokyo)

10km, mini ekiden

scroll for race details

the Eco Marathon ethos

bibs with timing chips reused each race

portion of entry fees donated to charity

lead runners led by bicycle

race day energy needs solar powered

Race Standard

  • Easy race day check-in

    Collect what you need to race on race day

  • Age Group awards

  • Event insurance

  • Race goodies (items vary by race)

  • Timed race results

    View official results online

  • Downloadable finisher certificate

  • Bag check (no valuables)

  • Aid stations (varies by race)

Samurai Sports Advantage

  • Easy registration

    Register in English without creating an account

  • Modify & transfer your entry

    Change categories, athlete to athlete transfer permitted, and self-edit up until 5 days before registration closes *fees may apply

  • English athlete guide

    The information you need to complete your race with peace of mind

  • English email support

    Ask questions - and get answers!

  • Post race follow-up

    Receive links to results, photos

about the Eco Marathon series

Steps Taken by the Race Organizer
・ Race bibs (including timing chip) can be collected and returned on race day. 
Staff and volunteers will wear face shields and masks
Hand sanitizer will be provided at the race venue. 
・All athletes must remain covered with a buff, mask, or similar face covering at all times at and within 100 meters of the race venue (including the start/finish area).
・No awards presentation. Results will be posted online. Awards will be mailed to winners.

Athletes must agree and abide to the following measures to prevent infection and the spread of COVID-19. 
・All athletes must wear a mask or face covering at the start/finish area and when walking to and from the race venue.

・Your failure to prepare and be informed does not constitute an emergency for others. Make sure to read through all of the event information below to understand the race details. Ask questions if you are uncertain.

General
・ No deferrals, credits, or refunds will be issued once registration has closed. This applies to incidents in which the race organizers are forced to cancel, postpone, or otherwise delay the event for the safety of athletes, staff, and volunteers. Such incidents include, but are not limited to severe weather, official emergency declarations, natural disasters (including earthquake), pandemic, biochemical or nuclear fallout, and personal circumstances of the participant (including illness, pregnancy, injury or similar catastrophe).
・Depending on the event, transfers and certain modifications to your entry may be permitted. Generally, entries may be transferable and/or permit modifications until 5 days before the last day of registration. After this period, all transfers are considered illegal and modifications will not be accommodated.
・Athletes may request a refund in writing via email, up until the last day of registration. Refunds will be processed online minus ¥2,000 transaction fees and administrative fees. 

Participants determined to be violating the policies below may be disqualified without a refund:
・Any person found to be bib-swapping (illegal transfer of bib); the person will be held responsible in case of an accident arising from or provoked by the other person during the event.
・Any person found to be registering with inaccurate information, i.e. false declarations of the participants name, age, or gender.

・You will not sue the event organizers nor its affiliates (including Samurai Sports) for any injury or death caused during the event.
・ You consent to and will give all authorities and copyright to the event organizer and affiliates for the use of photography, motion pictures, articles, recordings or any other record of this event (including personal information such as name, age, gender, personal record, portrait, and etc.) for legitimate purposes and use in newspapers, TV, magazines, internet and any media publishing such as Facebook posts, Instagram posts, and pamphlets.

Insurance
・ Those participating and coming from abroad must be enrolled in medical and/or travel insurance in case of accident, injury, and medical emergencies.
・ Before signing up, please carefully read all rules and regulations of the event. If the rules and regulations cannot be followed, participation may be denied by the event organizers. If anything is unclear, please do not hesitate to contact us – it is your responsibility to be prepared.

Race Organizer 
Eco Marathon
ecomarathon@runningintokyo.com
048-473-0898

Official Website
ecomarathon.run (Japanese only)

meet the race director

Juergen W.

A native of Germany, Juergen has called Japan home for the past 31 years. Passionate about environmental issues and sustainability, Juergen has taught the subject at Seoul National University and Keio SFC. In 2008, Juergen started the Eco Marathon series to provide an alternative running experience focused on social responsibility and giving back to the community. He has organized more than 100 races and is currently trying to set an age-graded PB at age 62 in his new carbon racers – the target is to get close to 1:30 for the half marathon.

2nd Adachi Eco Marathon

June 6, 2021

Arakawa, Tokyo

10km, 21.1km (road)

about the race

June 6, 2021 (Sunday)
at Arakawa City Baseball Field for Kids

0930-1030…athlete check-in
1030…race starts
1230…awards, closing ceremony
1400…
event ends (tentative)

10km
¥3,500 (¥4,000 incl. transaction fees)

21.1km
¥4,500 (¥5,000 incl. transaction fees)

Age Eligibility
・10km…must be 15 or older

Cut Off Times
10km…90 minutes 
21.1km…180 minutes 
・Must finish within 70 minutes (10km) or 150 minutes (21.1km) to view results online

Important
Maximum 300 athletes
・First come, first served.
Once the maximum number of athletes is reached, registration will close. 
・Be a responsible athlete. Please make sure you have the physical ability to complete the course.

10km, 21.1km
・The course takes place along the Arakawa River
・Course is flat, primarily asphalt, and can be very windy
・One lap is 7km
・One aid station will be available at the 3.5km turn around point

Start/Finish
・Adjacent to Ogi Ohashi bridge and the Arakawa City Baseball Field for Kids

扇大橋南下(荒川区少年運動場多目的広場隣)
Google Maps

By Train
・about 3 min. by foot from Adachi-Oida station

Parking
・None, vehicles parked illegally will be towed at the owner’s expense. Please use public transportation.

・Ensure you have transportation plans figured out BEFORE registering for this race.

・All participants are entitled to a Decathlon backpack
・All finishers are entitled to a neck gaiter (buff)
・No shirts or medals

10km
Top 6 overall men
Top 3 overall women
Champion age group awards

Age Groups
29 and under, 30-39, 40-49, 50-59, 60-69, 70-79, 80+

・Free bag check will be available at the start. Please do not bring valuables. 
・Your failure to prepare and be informed does not constitute an emergency for others. Make sure to read through all of the event information below to understand the race details. Ask questions if you are uncertain.

General
・ No deferrals, credits, or refunds will be issued once registration has closed. This applies to incidents in which the race organizers are forced to cancel, postpone, or otherwise delay the event for the safety of athletes, staff, and volunteers. Such incidents include, but are not limited to severe weather, official emergency declarations, natural disasters (including earthquake), pandemic, biochemical or nuclear fallout, and personal circumstances of the participant (including illness, pregnancy, injury or similar catastrophe).
・Depending on the event, transfers and certain modifications to your entry may be permitted. Generally, entries may be transferable and/or permit modifications until 5 days before the last day of registration. After this period, all transfers are considered illegal and modifications will not be accommodated.
・Athletes may request a refund in writing via email, up until the last day of registration. Refunds will be processed online minus ¥1,000 transaction fees and administrative fees. 

Participants determined to be violating the policies below may be disqualified without a refund:
・Any person found to be bib-swapping (illegal transfer of bib); the person will be held responsible in case of an accident arising from or provoked by the other person during the event.
・Any person found to be registering with inaccurate information, i.e. false declarations of the participants name, age, or gender.

・You will not sue the event organizers nor its affiliates (including Samurai Sports) for any injury or death caused during the event.
・ You consent to and will give all authorities and copyright to the event organizer and affiliates for the use of photography, motion pictures, articles, recordings or any other record of this event (including personal information such as name, age, gender, personal record, portrait, and etc.) for legitimate purposes and use in newspapers, TV, magazines, internet and any media publishing such as Facebook posts, Instagram posts, and pamphlets.

Insurance
・ Those participating and coming from abroad must be enrolled in medical and/or travel insurance in case of accident, injury, and medical emergencies.
・ Before signing up, please carefully read all rules and regulations of the event. If the rules and regulations cannot be followed, participation may be denied by the event organizers. If anything is unclear, please do not hesitate to contact us – it is your responsibility to be prepared.

Athlete Guides
・Athlete guides in English will be sent via email approximately 1-2 weeks before the event by the race organizer. 

12th Yodogawa Eco Marathon

November 21, 2021

Yodogawa, Osaka

10km, 21.1km

about the race

November 21, 2021 (Sunday)
at Yodogawa River Park Nishi-Nakajima area

0900-1000…athlete check-in
1400…
event ends (tentative)

10km
¥3,500 (¥4,000 incl. transaction fees)

21.1km
¥4,500 (¥5,000 incl. transaction fees)

Age Eligibility
・All categories…must be 18 or older

Cut Off Times
10km…90 minutes 
21.1km…180 minutes 
・Must finish within 70 minutes (1okm) or 150 minutes (21.1km) to view results online

Important
Maximum 500 athletes
・First come, first served.
Once the maximum number of athletes is reached, registration will close. 
・Be a responsible athlete. Please make sure you have the physical ability to complete the course.

All Categories
・Takes place along the Yodogawa River
・Course is flat and paved in asphalt – PR-friendly and beginner-friendly
・One lap is 5km
・One aid station at the 2.5km turn-around point

Start/Finish
Yodogawa River Park Nishi-Nakajima area
Google Maps

By Train
・about 5 min. by foot from Minami-Kata station (Hankyu Kyoto Line)
・about 6 min. by foot from Nishinakajima Minami-Kata station (Subway Midosuji Line)
・Walk south from either station; when you reach the embankment, turn left eastbound and walk straight. The race venue and start area is near the baseball field.

Parking
・None, vehicles parked illegally will be towed at the owner’s expense. Please use public transportation.

・Ensure you have transportation plans figured out BEFORE registering for this race.

・All participants receive a Decathlon 10-liter backpack
・No shirts or medals. Finisher certificates are virtual and can be printed at home.
・Bibs and timing chips are collected on-site and must be returned

21.1km, 10km
Top 3 overall men
Top 3 overall women
Champion age group awards

Age Groups
29 and under, 30-39, 40-49, 50-59, 60-69, 70-79, 80+

・An area for setting down personal belongings will be available. Please do not bring valuables. 
・Your failure to prepare and be informed does not constitute an emergency for others. Make sure to read through all of the event information below to understand the race details. Ask questions if you are uncertain.

General
・ No deferrals, credits, or refunds will be issued once registration has closed. This applies to incidents in which the race organizers are forced to cancel, postpone, or otherwise delay the event for the safety of athletes, staff, and volunteers. Such incidents include, but are not limited to severe weather, official emergency declarations, natural disasters (including earthquake), pandemic, biochemical or nuclear fallout, and personal circumstances of the participant (including illness, pregnancy, injury or similar catastrophe).
・Depending on the event, transfers and certain modifications to your entry may be permitted. Generally, entries may be transferable and/or permit modifications until 5 days before the last day of registration. After this period, all transfers are considered illegal and modifications will not be accommodated.
・Athletes may request a refund in writing via email, up until the last day of registration. Refunds will be processed online minus ¥2,000 transaction fees and administrative fees. 

Participants determined to be violating the policies below may be disqualified without a refund:
・Any person found to be bib-swapping (illegal transfer of bib); the person will be held responsible in case of an accident arising from or provoked by the other person during the event.
・Any person found to be registering with inaccurate information, i.e. false declarations of the participants name, age, or gender.

・You will not sue the event organizers nor its affiliates (including Samurai Sports) for any injury or death caused during the event.
・ You consent to and will give all authorities and copyright to the event organizer and affiliates for the use of photography, motion pictures, articles, recordings or any other record of this event (including personal information such as name, age, gender, personal record, portrait, and etc.) for legitimate purposes and use in newspapers, TV, magazines, internet and any media publishing such as Facebook posts, Instagram posts, and pamphlets.

Insurance
・ Those participating and coming from abroad must be enrolled in medical and/or travel insurance in case of accident, injury, and medical emergencies.
・ Before signing up, please carefully read all rules and regulations of the event. If the rules and regulations cannot be followed, participation may be denied by the event organizers. If anything is unclear, please do not hesitate to contact us – it is your responsibility to be prepared.

Athlete Guides
・Athlete guides in English will be sent via email approximately 1-2 weeks before the event by the race organizer. 

10th Nikotama Eco Marathon

September 12, 2021

Futako Tamagawa, Tokyo

10km, mini ekiden

about the race

September 12, 2021 (Sunday)
at Futako Tamagawa area

0900-1000…athlete check-in
1330…
event ends (tentative)

10km
¥3,500 (¥4,000 incl. transaction fees)

Mini Ekiden (2 athletes run 5km each)
¥5,000 (¥5,500 incl. transaction fees)

Age Eligibility
・10km, mini ekiden…must be 18 or older

Cut Off Times
10km…90 minutes 
Team Ekiden…120 minutes 
・Must finish within 70 minutes to view results online

Important
Maximum 300 athletes
・First come, first served.
Once the maximum number of athletes is reached, registration will close. 
・Be a responsible athlete. Please make sure you have the physical ability to complete the course.

10km, mini ekiden
・The course takes place along the Tama River (Tamagawa)
・Course is flat and paved in asphalt – PR-friendly and beginner-friendly
・One lap is 5km (see Strava map HERE)
・Mini ekiden requires two athletes, each running 5km
・One aid station at the 2.5km turn-around point

Start/Finish
Seta picnic area 
瀬田ピクニック広場
Google Maps

By Train
・about 5 min. by foot from Futako Tamagawa station
about 5 min. by foot from Futako Shinchi station

Parking
・None, vehicles parked illegally will be towed at the owner’s expense. Please use public transportation.

・Ensure you have transportation plans figured out BEFORE registering for this race.

・10km participants receive a Decathlon backpack
・Mini ekiden participants receive a Decathlon waist pouch
・All finishers are entitled to a neck gaiter (buff)
・No shirts or medals
・・Bibs and timing chips are collected on-site and must be returned

Mini Ekiden
Top 3 overall

10km
Top 6 overall men
Top 3 overall women
Champion age group awards

Age Groups
29 and under, 30-39, 40-49, 50-59, 60-69, 70-79, 80+

・An area for setting down personal belongings will be available. Please do not bring valuables. 
・Your failure to prepare and be informed does not constitute an emergency for others. Make sure to read through all of the event information below to understand the race details. Ask questions if you are uncertain.

General
・ No deferrals, credits, or refunds will be issued once registration has closed. This applies to incidents in which the race organizers are forced to cancel, postpone, or otherwise delay the event for the safety of athletes, staff, and volunteers. Such incidents include, but are not limited to severe weather, official emergency declarations, natural disasters (including earthquake), pandemic, biochemical or nuclear fallout, and personal circumstances of the participant (including illness, pregnancy, injury or similar catastrophe).
・Depending on the event, transfers and certain modifications to your entry may be permitted. Generally, entries may be transferable and/or permit modifications until 5 days before the last day of registration. After this period, all transfers are considered illegal and modifications will not be accommodated.
・Athletes may request a refund in writing via email, up until the last day of registration. Refunds will be processed online minus ¥2,000 transaction fees and administrative fees. 

Participants determined to be violating the policies below may be disqualified without a refund:
・Any person found to be bib-swapping (illegal transfer of bib); the person will be held responsible in case of an accident arising from or provoked by the other person during the event.
・Any person found to be registering with inaccurate information, i.e. false declarations of the participants name, age, or gender.

・You will not sue the event organizers nor its affiliates (including Samurai Sports) for any injury or death caused during the event.
・ You consent to and will give all authorities and copyright to the event organizer and affiliates for the use of photography, motion pictures, articles, recordings or any other record of this event (including personal information such as name, age, gender, personal record, portrait, and etc.) for legitimate purposes and use in newspapers, TV, magazines, internet and any media publishing such as Facebook posts, Instagram posts, and pamphlets.

Insurance
・ Those participating and coming from abroad must be enrolled in medical and/or travel insurance in case of accident, injury, and medical emergencies.
・ Before signing up, please carefully read all rules and regulations of the event. If the rules and regulations cannot be followed, participation may be denied by the event organizers. If anything is unclear, please do not hesitate to contact us – it is your responsibility to be prepared.

Athlete Guides
・Athlete guides in English will be sent via email approximately 1-2 weeks before the event by the race organizer.