Cybi Coastal Marathon
Race Day Weather
Cool conditions, watch for wind shifts
Runners will face a mild temperature range of 59°F to 60°F throughout the race. Winds will be a factor, with a crosswind affecting the first and fourth segments, and a headwind in the middle miles, especially from miles 11-19. Given the high humidity at 81%, pacing adjustments may be necessary to conserve energy. It's advisable to stay hydrated and prepare for potential gusts, particularly during the rolling sections.
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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.
