Inthanon 20 is a 20.0 km trail race of HOKA Chiang Mai Thailand by UTMB 2025 in Chiang Mai, Thailand. The race starts on December 4, 2025.
By gradient, 37% of the distance is uphill, 43% downhill and 20% flat. The longest climb runs 1.9 km at an average 6.0% grade (116 m of vertical). The longest descent runs 2.6 km at 11.5% (293 m of vertical). The steepest climb averages 26.6% over 0.3 km. The steepest descent drops at 28.4% over 0.4 km. Surface: 47% road, 41% trail, and 12% smooth. Flat-equivalent effort: 28.8 FlatKM.
The course is runnable enough that trekking poles are not needed.
Quad damage risk is low (index 13 of 100): a few descents worth noticing, none that decides the result.
Historically on race day, start temperatures range from 15°C to 21°C, around 17°C at the highest point; the chance of precipitation is about 7%.
721 finishers completed the 2025 edition. Men's winner: Hiroki Kai (Japan) in 1:43:52. Women's winner: Yuri Yoshizumi (Japan) in 1:53:41.
This page has the full results and splits, interactive elevation profile, gradient matrix, pacing and nutrition planner and weather climatology for Inthanon 20.
Other distances of HOKA Chiang Mai Thailand by UTMB 2025Chiang Dao 160 (168 km)·Elephant 100 (96.0 km)·Hmong 50 (56.0 km)·Hmong 50 Night (56.0 km)·Inthanon 50 (39.0 km)·Suthep 20 Night (21.0 km)·Suthep 20 Day (21.0 km)·Chedi 20 (17.0 km)
Other editions of Inthanon 202026
Official websitechiangmai.utmb.world
