Borneo Ultra Trail Marathon (BUTM): Race Guide
What is the Borneo Ultra Trail Marathon?
The Borneo Ultra-Trail Marathon (BUTM) is Sabah's flagship trail race, held each April in the Kiulu Valley. Its courses are ITRA-rated and qualify for UTMB World Series events. BUTM 2027 is on 3 and 4 April, with distances from 9 km to about 105 km.
What is the Borneo Ultra Trail Marathon?
The Borneo Ultra Trail Marathon (BUTM) is Sabah's leading trail and ultra-distance running event. Based in the Kiulu Valley north of Kota Kinabalu, it is organised by Borneo Ultra Trails Sdn Bhd and takes runners off the road and into the rainforest for a true wilderness challenge.
What sets BUTM apart from Sabah's other big races is its international standing in the trail community: its courses are rated by the International Trail Running Association (ITRA) and count as qualifiers for UTMB World Series events, putting it on the radar of trail runners worldwide (BUTM race information, checked 7 October 2026).
When and where is BUTM held?
BUTM is run in April in the Kiulu Valley. The 2026 race was on 11 and 12 April (Sabah Tourism Board, checked 7 October 2026), and BUTM 2027 is on 3 and 4 April 2027 (BUTM registration page, checked 7 October 2026). Since 2026 the start and finish have been at SMK Tun Fuad Stephens in Kiulu, because the usual Kiulu Riverside Park is closed for construction of a new road bridge (BUTM race information, checked 7 October 2026). The organisers' course notes say streams rose significantly in the very wet conditions of 2025 (BUTM course maps, checked 7 October 2026), so prepare for rain and slippery footing.
Distances and categories
For 2027 the organisers list these approximate distances (BUTM race information, checked 7 October 2026):
| Distance | Best for |
|---|---|
| 105 km | Experienced trail runners |
| 55 km | Intermediate trail runners |
| 34 km | Intermediate trail runners |
| 9 km (Sunday) | Newcomers and families; non-competitive except a youth category |
Entry fees, early-bird deadlines and optional bus transfers are listed on the BUTM registration page.
The UTMB and ITRA connection
For serious trail runners, BUTM's biggest draw is its ITRA rating. The organisers expect the 2027 courses to carry 5 ITRA points for the 100 km, 3 for the 50 km and 2 for the 30 km, and these ITRA-rated courses count as qualifiers for UTMB World Series events. BUTM 2027 is also part of the Asia Trail Master Championship, and the 100 km is a qualifier for the 2028 Western States 100-mile Endurance Run (BUTM race information, checked 7 October 2026).
What the terrain is like
BUTM is a genuine off-road event. Runners tackle jungle trails, dirt tracks, river crossings and ridgelines around the Kiulu Valley, and the 100 km follows a figure-of-eight with a halfway station at Kiulu (BUTM course maps, checked 7 October 2026). Underfoot conditions range from packed earth to mud and rock, and the rainforest brings heat and humidity that can sap energy fast. This is a course where navigation, footing, and heat management matter as much as raw speed.
Preparing for BUTM
Trail-specific preparation is essential. Road fitness alone will not carry you over technical jungle terrain and climbs.
Build strength on hills and technical descents, practise running in heat and humidity, and rehearse with the mandatory kit and hydration you will carry. Recce the river crossings if you can, and plan your nutrition for the longer distances where time on feet stretches into many hours.