Cybi Coastal Marathon
Race Day Weather
Mild temps, moderate humidity
Runners will face temperatures starting at 60°F and peaking at 64°F. With an average humidity of 72% and a steady wind from the SW at 17 mph, hydration will be crucial. Runners should adjust their pace conservatively to account for the humidity and consider gear that minimizes wind resistance.
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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.
