Cybi Coastal Marathon
Race Day Weather
Mild temps, variable wind conditions
Runners will face a temperature trend starting at 59°F and finishing at 60°F while contending with a maximum wind of 13 mph from the WSW. With average humidity at 81%, it's advisable to start conservatively, especially during the critical climbs from miles 22 to 23. The changing wind direction will require attention to pacing, particularly during the headwinds from miles 11 to 19.
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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.
