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Ecomarathon of Saïko in December 2026

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The event in a few words

Get ready for the Saïko Ecomarathon, a sporting experience in December in the heart of Saitama Prefecture in Japan 🇯🇵. It's precisely in the city of Toda, by the Lake Sai, in the Doman Green Park, where you'll start at 11 AM sharp! 🕚 Therefore, you're set for two races of your choice: a half-marathon or a 10 km, both in the format of a loop. If you came with family 👨‍👩‍👧‍👦, a 5 km parent-child race is organized. The course also takes the format of a loop 🔂. You can enjoy a route surrounded by lakes, ponds, and magnificent nature 🍃. You will be immersed in a peaceful and inspiring environment, perfect for breaking your personal record or simply enjoying every stride 💪.

With several other sporting events organized, especially in the prefectures of SaitamaOsakaHiroshimaKyoto and Kumamoto (but mainly in Tokyo 🌸), the Ecomarathon positions itself as an organization concerned about the environment 🌳 and committed to various causes 🎗️. This year, it is possible to donate to the international refugee aid associationSecond Harvest Japan. Japan's first food bank, the organization is committed to ensuring everyone has access to food 🍲.

Despite its urbanization, the Saitama Prefecture remains significant for its agriculture. It includes vegetable 🥦, rice 🍚, and tea 🍵 productions. There, you can taste the famous Sayama tea, Udon and Chichibu Soba, or Senbei from Sōka. Once you’ve regained your strength, why not do some tourism ? Located in Omiya, the Hikawa Shrine is one of the oldest and most respected Shinto shrines in Japan. To learn more about Japanese culture 🫰, the Saitama Prefectural Museum of Art is full of various collections of Japanese and Western art 🖼️. If you don't have time to extend your stay, the city of Toda also offers activities that will please you. For a great family outing, do not hesitate to visit the Tobu Zoo to admire its animals 🐼 and try its roller coasters 🎡. If you're just passing by for the day, Tokyo, the capital of the country, is only 20 minutes away. Whether you are interested in traditional culture, fashion, cuisine 🥢, or simply the hustle and bustle of urban life, you're unlikely to get bored! 😉

Don't miss this opportunity to combine sports, nature, and cultural discovery in a stunning region of Japan! 🎐 Sign up now and get ready to have an unforgettable experience at the Saïko Ecomarathon 🎏.

4 reasons to join this race

Discover Japan 🇯🇵
If you have never been to Japan, running the Saiko Ecomarathon is the perfect opportunity to explore this country that blends tradition and modernity in all circumstances. If you decide to extend your stay, we invite you to explore the Saitama Prefecture. From Kawagoe Castle 🏯 to the Tobu Zoo 🐼 and the Onsen 🚰, these attractions are well-known.
Taste Japanese specialties 🍱
Here are some specialties you'll surely see if you pass by the street stalls 🎏. Gokabo is one of the three main desserts of Saitama Prefecture. Sayama tea is a must in the region, and if you're lucky, you might even witness the famous tea ceremony 🍵.
Immerse yourself in Japanese culture 🫰
Saitama Prefecture is very present in mangas and animes 🖥️. Scenes from "My Neighbor Totoro" (Hayao Miyazaki) are set near Tokorozawa, the protagonist of the anime One Punch Man is named Saitama (where its author hails from), and the fictional world’s continent mirrors the shape of the prefecture 🤯.
An easy, flat, and fast course ⚡️
You might be surprised by the ease and speed of the 10 km course. Indeed, it is perfect for beginners and those hoping to break records 🏆. If you aim to spend a Sunday with family, a parent-child race is organized for children under 15 🧑‍🧑‍🧒‍🧒.

A distance for every taste

Frequently asked questions (FAQ)

Bib pickup will be on-site on race day from 9 AM to 10:30 AM.

The races will start at 11 AM on December 28, 2025, at Doman Green Park.

  • Half Marathon: the time limit is 3 hours

  • 10 km: the time limit is 1 hour 30 minutes

You will find a designated area to store your luggage on-site (but no lockers, you will be entirely responsible for your valuables). Remember to bring a 45L garbage bag to protect your belongings in case of rain.

If you have any other questions, you can contact the organizers at the following email address: ecomarathon@runningtokyo.com

Focus

Ecomarathon de Saïko
Ecomarathon de Saïko
Ecomarathon de Saïko
Ecomarathon de Saïko
Ecomarathon de Saïko