Cardiff Half Marathon
Race Day Weather
Cool start, moderate wind challenge
Runners will face a temperature range from 55°F to 61°F with moderate winds from the WSW at 15 mph, gusting to 32 mph. Humidity sits at 77%, which may feel sticky. It's advisable to start conservatively and consider hydration strategies to combat the humidity.
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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 London's. 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.
