Amazean Jungle Thailand by UTMB
Amazean Jungle Thailand by UTMB – JUNGLE 50K
Betong Mongkollit Tunnel → Betong Clock Tower
Race guide
Updated 18 July 2026
The JUNGLE 50K is the middle-distance option at Amazean Jungle Thailand by UTMB, covering 55 km with 2,116 m of climbing and a high point of 991 m. Starting at the Betong Mongkollit Tunnel and finishing in town at the Betong Clock Tower, it packs the character of the region's bigger races — humid jungle trail, sustained climbs, and technical descending — into a distance most trail runners can complete in a single long day. With just two intermediate cut-offs and a finish deadline of Saturday 21:00, the JUNGLE 50K is a challenge of steady all-day movement in the heat rather than a flat-out race. It shares its early aid stations with the longer distances, so you get the same jungle atmosphere and well-spaced support without committing to a hundred-mile night out.
The course: 55 km from tunnel to clock tower
The JUNGLE 50K runs from the Betong Mongkollit Tunnel at 277 m to the Betong Clock Tower, also at 277 m, so the start and finish elevations match exactly and the 2,116 m of climb is spread across a rolling, up-and-down profile. The first section is the most forgiving: from the tunnel to A1 Kapae Hulu School at 11.2 km (338 m) and on to A2 Suan Palm Resort at 21.6 km (310 m), the net elevation barely moves, giving you a long window to warm up before the real climbing begins. The heart of the course lies between A2 and A3 Ai Yoe So Village at 35.8 km (461 m), where the route gains ground toward the 991 m high point. After A3 the course tips down and back up through A9 Thumthong Temple at 45.3 km (422 m) before the final 9.7 km descent into Betong. With aid stations spaced roughly 10 to 14 km apart, you will want to carry enough fluid and food to bridge each gap comfortably in the heat.
The decisive middle section
The race is shaped in the 14 km between A2 Suan Palm Resort at 21.6 km (310 m) and A3 Ai Yoe So Village at 35.8 km (461 m). Although the net elevation change between those two aid stations looks modest, this is the stretch that carries you up to and over the day's 991 m high point — a proper climb through jungle terrain that comes when the day is at its hottest. Runners who spent the flat opening 21 km too aggressively tend to unravel here. From the high point the course descends toward A9 Thumthong Temple at 45.3 km (422 m) and then drops steadily to the 277 m finish at the Clock Tower. That closing descent of nearly 10 km is where fresh legs pay off, so the smart play is to hold back on the runnable early kilometres, climb the middle patiently, and save something for a strong, controlled downhill finish rather than braking your way down on trashed quads.
Pacing and fuelling to the cut-offs
There are two intermediate cut-offs to respect: A2 Suan Palm Resort closes Saturday 12:00 and A9 Thumthong Temple closes Saturday 19:00, with the Betong Clock Tower finish at Saturday 21:00. That leaves a comfortable-looking window on paper, but the heat and the mid-course climb can slow you dramatically, so treat the A2 cut-off as a checkpoint on your early pacing rather than a formality — reaching it with time in hand means the climb to A3 will not become a race against the clock. Because aid stations sit roughly 10 to 14 km apart, plan your carrying capacity around the longest gap and drink to thirst plus a margin in the humidity. The Betong Clock Tower finish is a crew point, so arrange to meet support there, but the intermediate stations on this distance are not flagged as crew points — carry your own nutrition and electrolytes and top up fully at each aid station rather than skipping through. Eating consistently on the flat opening kilometres sets you up to climb well through the middle.
Conditions to expect
Set in the jungle around Betong in Thailand's far south, the JUNGLE 50K is defined by heat and humidity. Even though the distance is manageable, the sultry air raises your effort at any given pace and makes fluid and electrolyte management the single biggest factor in how your day goes. Expect thick, warm conditions in the lower sections near the tunnel and finish, with cooler and potentially misty air on the climb toward the 991 m high point. Jungle trail here means wet, root-laced and sometimes slick footing, so choose shoes with dependable grip and protect against blisters and chafing before they start. Depending on your speed you may run the closing kilometres toward the Saturday 21:00 finish in fading light, so carrying a headlamp is a sensible precaution. Runners who respect the humidity, fuel steadily, and stay patient on the middle climb will find the JUNGLE 50K a rewarding introduction to the Amazean Jungle terrain.
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Checkpoints & cut-offs
✓ Course data verified against the official source (2026-07-17) · official source
0 km · 277 m · —
11.2 km · 338 m · —
21.6 km · 310 m · Sat 12:00
35.8 km · 461 m · —
45.3 km · 422 m · Sat 19:00
55 km · 277 m · Sat 21:00
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