Cardiff Half Marathon
Race Day Weather
Comfortable temps, moderate wind
Mild 56°F temps at gun time mean comfortable early miles without overheating risk. Moderate winds around 15mph may affect pacing on open sections of the course. Moderate humidity at 78% is worth noting for effort level, especially in later miles.
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Race Info
The Cardiff Half Marathon takes place in Cardiff, Wales, each October and ranks as the UK's second-largest half marathon behind the Great North Run. The course starts on Castle Street beside Cardiff Castle and finishes near Cardiff City Hall in Cathays Park, passing Cardiff Bay and Roath Park Lake along the way. World Athletics has held it as an Elite Label road race since 2017, and the course hosted the IAAF World Half Marathon Championships in 2016. The race began in 2003 and has grown from about 1,500 finishers to more than 27,000.
