The Course: Out of the Old City and Across the River
All three races start and finish on Burapha Road beside The Old Siam Plaza, in Bangkok's old city [1]. The half marathon heads north past the City Pillar Shrine and Sanam Luang, crosses the Chao Phraya on the Phra Pinklao Bridge between about 2 and 4 km, and runs out past Central Plaza Pinklao at about 6 km to a U-turn near the Taling Chan post office at about 10 km [2]. It comes back the same way, recrossing the bridge at about 18 km. The map also marks the Borommaratchachonnani elevated road near the 14 km point [2].
The 10 km uses the same road over the bridge to a U-turn at about 5 km [3]. The 4 km fun run is a short out-and-back to Sanam Luang that stays on the old-city side of the river [4]. AIMS, which certified the 21.1 km and 10 km courses in 2020 [5], lists the race as a full member [6]. Its 2025 preview describes a course past Saranrom Park, the Grand Palace, the Ministry of Defence and the City Pillar Shrine, and calls one stretch "a unique elevated car-free bridge" [7]. The route maps carry no elevation profile.
The Weather: Warm, Saturated Air Before Dawn
Don Mueang airport, about 22 km north-north-east of the start, recorded 26°C at 3.30am, when the half marathon started, with a dew point of 23°C, 84% humidity and a 4-knot wind [8]. At 4.30am, for the 10 km start, it was still 26°C, with 89% humidity. From 5am it held at 25°C with a dew point of 24°C and 94% humidity, and the airport reported mist from 5.30am until after the 7am close [8].
A dew point of 23°C to 24°C is heavy air for running: sweat barely evaporates, so the temperature flatters the conditions. The early start keeps you out of the sun, but not out of the humidity. Start slower than your usual half-marathon pace and drink at every station.
Aid Stations and Cut-offs
The route maps promise water every 2 km [2]. On the half marathon there is water and first aid at 2, 4, 6, 8, 10, 12, 14, 16, 18 and 20 km, with electrolyte drinks and fruit at 8 km, 16 km and the finish, and toilets at 10 km and the finish [2]. The 10 km has electrolyte and fruit at 6 km [3].
Every race closes at 7am. That gives the half marathon three and a half hours from its 3.30am start, the 10 km two and a half hours and the 4 km one hour 45 minutes [9]. In 2026 the slowest half-marathon finisher took 3:22:21 and the slowest 10 km runner 2:18:38 [10][11].
Entries cannot be transferred. The entry terms say runners caught using another runner's bib are disqualified and removed from the race without a refund [1]. The results mark 29 half-marathon runners and 21 10 km runners as disqualified [10][11].
How Fast the Field Is
Aekkalak Jhankaeo won the half marathon in 1:18:12, from Narongchai Sookthong (1:19:52) and Watcharin Roensa (1:21:19). Nuchanat Engchuan won the women's race in 1:34:41, from Ka Yee Cheung (1:35:49) and Titayapa Meenapinunt (1:37:26) [10]. The winners took the Princess Maha Chakri Sirindhorn Trophy [12]. These were slower winning times than in 2024, when the half was won in 1:10:22 and 1:27:15 [5].
Tenth place was 1:24:55 for men and 1:45:50 for women, and the median finisher took 2:14:53 among men and 2:35:43 among women [10]. For the 30th edition the organiser gave a Fast Runner Appreciation Trophy to the 30 fastest men and 30 fastest women after the podium in both timed races [13]. On gun time, the 33rd man ran 1:32:35 and the 33rd woman 1:59:03 [10], so a woman breaking two hours won a trophy. Age-group trophies go five deep, and prize money for the half is 5,000, 3,000 and 2,000 baht [1].
The Bangkok Post and AIMS both put the 2026 field at 4,800 runners across the three races, a record according to AIMS [14][12]. Of those, 2,810 finished the two timed races [10][11]. The half is mostly local: 1,379 of the 1,483 half-marathon finishers were Thai, from 33 nationalities in all [10]. The 10 km was won by Russia's Ilia Zmaznev in 31:46 and Britain's Lyndsey Fraser in 38:25, and tenth place was 38:40 for men and 47:09 for women [11].
Race Weekend Logistics
Race packs were collected on Saturday 31 January, from 10am to 6pm, at the Gurudwara Sri Guru Singh Sabha, the Sikh temple of the race's organiser, Sri Guru Singh Sabha [1]. A friend can collect for you with a copy of your ID card or passport, and postal delivery cost 60 baht per person, with dispatch from 10 January [1].
On race morning there was free parking from 2.30am to 8am at The Old Siam Plaza and the Ruam Thanu Thai Building; runners had their tickets stamped at the event information tent [1]. The opening ceremony and warm-up began at 3.15am [1].
Regular entry cost 500 baht for the 4 km, 600 baht for the 10 km and 700 baht for the half, until 15 December 2025 [9]. Every entry included a race shirt, a medal, a bib, food and drink and accident insurance; the 10 km and half added chip timing and an e-certificate, and only half-marathon finishers got a finisher shirt [15]. Fees are not refunded once an entry is confirmed, including if the race is cancelled or postponed [1]. The AIMS preview describes the post-race meal as unlimited food and drink, in the Sikh tradition of langar, the community kitchen [7].
Should You Enter the 2027 Race?
Yes, if you want a cheap, certified half marathon or 10 km through Bangkok's old city, with a limit that suits slower runners and trophies that reach well down the field. The 4 km suits families: AIMS reported children aged 3 to 10 on the course in 2026 [12].
Think twice if you want a big field around you, since fewer than 1,500 finished the half, or a personal best in cool air. At 3.30am in 2026 the dew point was already 23°C, and the half is a single out-and-back, so the second half repeats the first.
The 31st edition is on Sunday 31 January 2027 [6], again listed on Burapha Road at The Old Siam Plaza [1]. Check the 2027 fees, start times and route maps before you enter.
Nobody from this site ran the race. This review draws on the organiser's race information and route maps, the full results, AIMS reports, Bangkok Post reporting and airport weather records.