About This Race
The 163K represents Ultra-Trail Snowdonia's ultimate endurance test, demanding exceptional preparation and mental fortitude as runners navigate the full mountain circuit through two complete days and nights. This distance requires mastery of pacing and nutrition strategies across Snowdonia's unforgiving terrain, where the technical rocky sections and exposed ridges become exponentially more challenging as fatigue accumulates over 30+ hours. Designed for experienced ultra-runners seeking their next progression in mountain endurance, the 163K offers a grueling apprenticeship for those targeting the world's most demanding ultra-trail events.
Practical Info
Variable mountain conditions typical of North Wales in May, with potential for rain, wind, and temperature changes with elevation
MAN - Manchester Airport
Llanberis offers various accommodation options from B&Bs to hotels, with additional lodging available in nearby Snowdonia villages
Best For
Notable Features
As part of the UTMB World Series, this race maintains the highest standards of organization and course design. The event showcases the dramatic landscapes of Snowdonia National Park through technical single track that demands both fitness and technical skill. The multi-day format creates a festival atmosphere in the historic mountain town of Llanberis, complete with family activities including the ERYRI MINI kids' race.