Bangsaen21
Race Day Weather
Warm start
A warm 72°F start means heat management is critical — consider dialing back your goal pace by 10-20 sec/mi. Temperatures rising to 81°F through the course will gradually increase perceived effort in the second half. Light winds shouldn't be a major factor for pacing. Moderate humidity at 76% is worth noting for effort level, especially in later miles.
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Race Info
Bangsaen21 is an annual half marathon held along Bang Saen Beach in Chon Buri Province, Thailand, first run in 2005. It carries a World Athletics Platinum Label, the sport's top distance-running distinction, and was Thailand's first race to earn that label. The race starts before dawn on the beachfront road in Bang Saen, loops out along Bangsaen-Angsila Road, and finishes back on the beach promenade. Course records were set in 2022, when Kenya's Josphat Kemei ran 1:01:56 and Hellen Obiri ran 1:07:45.
