The setting is the mountainous area of Chichibu and Okumusashi in the southwestern part of Saitama Prefecture.
This year marked the 10th "FunTrails Round Chichibu & Okumusashi (FTR)". Chichibu & Okumusashi). The Chichibu-Okumusashi area in the southwestern part of Saitama Prefecture is a mountain range of low mountains less than 1,000 meters above sea level, where well-maintained trails spread out like a meshwork.

There are three categories: 100 miles, 100 km, and 50 km. The "Hui-Nam Running Club♡" members participated in the 100 km category this time.

Hideki Shibayama (left), editor of Huinum, and Hiroshi Yamamoto (right), deputy editor of Huinum
This is Shibayama's first time participating in a trail race over 100 km. The longest race he has completed in the past is 65 km.
Yamamoto has experience completing ultra-distance trail races such as 100 km and 100 miles. He also completed Japan's leading ultra trail race, Mt. FUJI 100 (formerly UTMF) in 2018.
FTR" in which the two will be competing this time The 100-kilometer section of the "Chichibu & Okumusashi" race in which the two runners will compete is 105 kilometers in total distance and has a cumulative elevation gain of 6,831 meters. Those who are familiar with trail running can imagine how tough this race is. There are not many races with such a large cumulative elevation gain relative to the distance.

The race starts at 6:00 a.m. on November 16, and participants must pass through the finish gate by 2:00 p.m. on the following day, November 17. In addition, there will be 8 gates set up along the course, and if a single second passes the time limit, the contestant will be disqualified on the spot.
The completion rate for the 100-kilometer division of the last race was approximately 68%. To qualify for the 100-kilometer division, runners must have completed at least one trail running race of 100 km or more or two trail running races of 50 km or more within the specified time frame, as determined by the organizer. Even with such strict requirements, approximately 30% of the contestants fail to reach the goal in this grueling race. That is the "FTR Chichibu & Okumusashi" 100km race.