Snowdonia Marathon Eryri
Race snapshot
Race Day
45–54°F · Feels cool
Total elevation gain
Very hilly terrain · Net elevation change +0 ft
Participants
Medium-sized race
Crowd Rating
Excellent spectator turnout
The Lowdown
Snowdonia Marathon Eryri is a legendary road marathon that circles Yr Wyddfa (Snowdon), the highest peak in Wales, starting and finishing at the Electric Mountain Event Village in Llanberis. First run in 1982, it is widely regarded as one of the toughest road marathons in the UK: the course follows the A4086 and climbs steadily to the top of the Llanberis Pass before dropping to the Pen-y-Gwryd junction, threading past Beddgelert, and climbing again to roughly 1,200ft at Bwlch y Groes before a long descent back into Llanberis. Total elevation gain is around 788m (2,585ft) over closed mountain roads, with 12 feed stations along the route. The race is capped and typically sells out; public entry for the 2026 (42nd) edition ran through a ballot open 1-8 December, with unsuccessful/late entrants placed on a waiting list. Only bone-conduction headphones are permitted (per UKA rules) because runners share single-track sections of road. Roughly 2,500-3,000 runners take part each year, drawn by the spectacular Snowdonia National Park scenery and the brutal late-course climbs.
Explore the course
Edition unconfirmed · Marathon
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