Cybi Coastal Marathon
Race Day Weather
Cool temps, watch for wind shifts
Runners will face a temperature range of 58°F to 60°F, with humidity at a high 81%. Wind will be a factor, starting with a crosswind and shifting to a tailwind in the latter miles, peaking at 13 mph. It’s advisable to pace conservatively, especially through the hilly segments from miles 22 to 23, and maintain hydration due to the humidity.
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Race Info
The Cybi Coastal Marathon is a 26.2-mile trail race around Holy Island (Ynys Cybi) on the north Wales coast, starting and finishing at the RNLI station on Newry Beach in Holyhead. The route follows the Anglesey Coastal Path past South Stack lighthouse, Silver Bay, Rhoscolyn, and Trearddur Bay before a climb over Holyhead Mountain (Mynydd Twr). A shorter 25-kilometer option, the Half Cybi, follows the same course until diverging near Penrhos. Entries are capped at roughly 200 runners per distance and open each January 1, benefiting the RNLI Holyhead and Trearddur Bay lifeboat stations.
