The Course: Out Along the Coast, Back Over the Headlands
Bangsaen42 has one race only, the marathon [1]. It starts and finishes on the beach road in front of the Bangsaen Heritage Hotel [2]. On the official 2025 map the route runs south along the beach, loops inland to Sukhumvit Road and back through town in the first 16 km, then follows the coast road north to a U-turn at 21.1 km. The second half comes back past Ang Sila, around Khao Sam Muk and Laem Taen, and finishes with a last stretch beside Bang Saen beach [2].
The organiser describes the route as heading to the Chonlamarkwithi Bridge, a coastal road, and including the climb of Khao Sam Muk [1]. The map's elevation strip puts the total climbing at 88 m [2]. A Thai running blog says runners call the bridge the soul-sucking bridge, because many start to hurt or drop out there, and describes Khao Sam Muk as a hill that tests runners in the late stages; it also lists the Bang Saen roundabout, the giant mortar at Ang Sila and the Nezha shrine among the landmarks on the way [3].
The course is certified by World Athletics in cooperation with AIMS [2], the organiser says finish times can be used as Boston Marathon qualifiers, and the race has held a World Athletics Elite Label since 2021 [1]. With the first wave away at 2.30am [4] and a median finishing time of about 5 hours 21 minutes [5], a typical runner finished at around 8am.
The Weather: Saturated Air Before Dawn
The nearest airport weather stations are some way from the start: Suvarnabhumi, about 50 km north-west, and U-Tapao, about 70 km south on the same coast. At 2.30am on race morning Suvarnabhumi recorded 27°C, a dew point of 26°C, 94% humidity, a 3-knot wind and mist [6]. U-Tapao recorded 25°C with a dew point of 25°C: 100% humidity [7].
It barely changed until dawn. Suvarnabhumi stayed at 26°C to 27°C and 94% to 100% humidity until 7am, then warmed to 28°C at 8am, 30°C at 9am and 31°C at 10am, when the finish closed [6]. U-Tapao was still at 100% humidity at 8am and reached 30°C by 8.30am [7].
A dew point of 25°C to 26°C is about as oppressive as running air gets: sweat hardly evaporates, so the bridge and the late climb cost more than their height suggests. After the 2025 race one finisher spent six days in hospital with rhabdomyolysis, a dangerous breakdown of muscle, and acute kidney injury. They crossed the line with a fever of 38.1°C, said they felt foggy and remembered only parts of the last stretch, and could not find race staff at the finish [8]. Start well below your cool-weather pace and know where the medics are: the 2025 map shows a medical point at most stations [2].
Aid Stations and Cut-offs
The 2025 map shows a water station about every 2 km from 4 km to 40 km, most with electrolyte drinks, toilets and a medical point. There were energy gels at a few stations, bananas and snacks at 30 km, watermelon at 36 km, and shower points at 34 km and 40 km [2]. Local cheer squads under the name Chonburi We Cheer lined the route with lion dances, Thai dancing and bands [9], and the race director said residents came out to hand runners water and snacks [10].
The time limit is seven hours, counted from the last wave at 3am, and there are five cut-offs on the way: 10 km at 4.45am, halfway at 6.30am, 30 km at 7.56am, 35 km at 8.46am and 40 km at 9.36am, with the finish closing at 10am [2][1]. Runners who miss a cut-off are not allowed to continue, are taken back by a sweep shuttle, and get no medal or finisher shirt [1]. Because the limit runs from the last wave, runners in the 2.30am wave had seven and a half hours: the results list 100 finishers with net times over seven hours, which points to that extra time being used [5].
In 2025, 674 starters did not finish and 1,630 entrants did not start [5].
Roads and the Start Pens
The Saen Suk mayor said the course would be 100% closed to traffic, in line with the Elite Label standard [11], and parking was banned on the roads leading to the beach because they formed the course [4]. The provincial organisers said they had resurfaced roads and added lighting along the route [11].
The start area opened at 12.30am and the start line closed at 3.10am; late runners were not let through. Runners had to start from their assigned block, and climbing a fence into another block counted as a serious offence punishable by disqualification [4]. Race packs were checked with a Face ID system at pickup, and bib transfers were banned outright [12].
How Fast the Field Is
Kenya's Laban Kiplimo won in 2:17:53, ahead of David Barmasi Tumo in 2:18:18 and Muhia Alexander Njai in 2:18:20. Truphena Chepchirchir of Kenya won the women's race in 2:44:48, from Ethiopia's Alemtsehay Mekuria Alamirew in 2:45:11 and Meseret Tafa Gemechu in 2:45:26. The first Thais were Anuchit Jiw in 2:37:03 and Piyanuch Sukchat in 3:04:03 [10]. The field included 23 elite and 10 semi-elite runners, plus 174 Thai fast runners [11].
Behind them the field thins quickly. Tenth place was 2:27:39 for men and 3:12:20 for women; only 55 men and 7 women broke three hours, and the median finisher took 5 hours 21 minutes [5]. The race's King Kong award, a mascot figure for the first 100 men and 100 women [11], went down to 3:08:01 for men and 3:54:22 for women in 2025 [10]. Thai runners who break the Thai course records, 2:22:26 for men and 2:52:30 for women, earn a 100,000-baht bonus [11].
Of the 9,729 finishers, 1,849 were women and 9,567 were Thai; the results show runners from 35 countries [5], while the tourism authority put the field at 37 countries [11].
Race Weekend Logistics
General entry in 2025 included a lottery for 4,000 places. The 1,400-baht ticket meant collecting your bib on Friday 7 November, 12pm to 8pm, only; the 1,600-baht ticket allowed Friday or Saturday [13]. International runners could buy a guaranteed place for 2,000 baht, or 3,500 baht as a semi-elite with a marathon under 2:50 (men) or 3:20 (women); if they could not come, they could take a partial refund or have the race kit posted [12].
The provincial organisers said hotels in Bang Saen, Si Racha and nearby were fully booked for race weekend [11]. On race morning there were four car parks: 800 spaces on the football field behind the Bangsaen Heritage Hotel (open until 1.30am), 300 in the Saen Suk municipal car park, and roadside parking on Khao Lam Road and Bangsaen Sai 2 Road, served by red songthaew shuttles until 2.45am and 2.30am. Drop-offs were at the Khao Lam junction near the hotel. Return shuttles ran from Bangsaen Soi 3 from 7am to 11.35am, and the organiser asked runners to arrive at least two hours before their start [4].
Should You Enter the 2026 Race?
Yes, if you want a big marathon-only field on closed roads, a certified course for a qualifying time, and a seven-hour limit that suits steady runners. It also suits Thai club runners chasing a King Kong place or an age-group trophy.
Think twice if you struggle in humid air, if you need a flat course (the climb at Khao Sam Muk comes late), or if you would be close to the intermediate cut-offs, which are enforced on the clock.
The 2026 race, the 10th, is on Sunday 15 November with 12,000 places, the same 2.30am, 2.45am and 3am waves and the same seven-hour limit from the last wave. Bibs must be collected in person on Friday 13 or Saturday 14 November; there is no race-day pickup. The regular fee is 2,000 baht, with a 1,600-baht rate for loyalty and lottery runners and 2,000 baht for guaranteed international entry, plus a 50-baht processing fee [1].
Nobody from this site ran the race. This review draws on the organiser's 2025 race map, transport guide and 2026 race information, the entry pages, the full results, airport weather records, Thai press reports and a Thai running blog.