The Okumusashi Long Trail Race begins and ends at Hanno City Central Park and Civic Hall, sending runners into the Okumusashi mountains near the Tokyo metropolitan area. This is a two-day mountain trail race held in May, offering 105K, 105K pair, 35K, and 20K categories. The main 105K event involves over 8,000m of climbing, making completion a significant challenge.
The race was established by local residents in collaboration with Hanno City and five mountain districts, and Creator 9000 Inc. manages the event. The 20K option provides a beginner-friendly course starting from Hanno Central Park and going through Mt. Tonomine. The 105K pair category offers a more communal approach to the full-distance course. Historical finish rates illustrate the varying difficulty: the 105K typically sees completion rates between 60-63%, whereas the 20K reaches 83%. A documentary film covering the third running, Rikyo Okumusashi, can be found on YouTube, and the event also shares essential mountain safety information, including advice on bear encounters.