The Big Half
Race Day Weather
Warm climb, adjust pace wisely
Runners will face a temperature increase from 62°F at the start to 80°F by race end, with average humidity at 51%. There will be a crosswind during the first seven miles and headwinds in Miles 8 and 11, which may impact pacing. It is advisable to pace conservatively in the early miles and stay hydrated, especially as temperatures rise.
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Race Info
The Big Half is a half marathon through central and southeast London, organized by London Marathon Events, the team behind the TCS London Marathon. First held in 2018, the race starts on The Highway near the north side of Tower Bridge, loops east through Limehouse toward Canary Wharf, then crosses Tower Bridge and runs through Bermondsey, Rotherhithe, and Deptford to finish beside the Cutty Sark in Greenwich. The half is the centerpiece of a community-focused race day that also includes the one-mile Big Mile fun run and the New Balance Big Relay team event.
