About This Event
Part of the prestigious UTMB World Series, Ultra-Trail Snowdonia delivers a feast of technical trails through the mythical landscapes of North Wales. The event showcases the rugged wilderness of Snowdonia National Park, where over 2,800 runners from more than 60 nationalities test themselves against some of Britain's most challenging mountain terrain. Based in Llanberis, the race offers multiple distances that wind through ancient Welsh landscapes steeped in Celtic legend and natural beauty. The technical nature of the courses demands respect, with rocky ascents, exposed ridges, and weather that can shift dramatically throughout the event weekend. The tagline 'Beautiful beyond belief. Savage beyond reason' captures the dual character of this mountain running experience. As a UTMB World Series event, Ultra-Trail Snowdonia attracts an international field seeking both the challenge of Snowdonia's peaks and the qualifying points for the original UTMB in Chamonix. The event weekend includes races spanning three days in May, creating a festival atmosphere in the shadow of Wales' highest peaks.
Choose Your Distance
25K
The 25-kilometer introduction to Ultra-Trail Snowdonia features 1,400 meters of elevation gain. This Running Stones 1 category race offers newcomers a taste of Welsh mountain running without ultra-distance commitment.
56K
The route ventures into the heart of Eryri National Park, weaving through terrain that has tested mountain runners for generations. Expect sustained technical sections where route-finding instincts and scrambling comfort pay dividends. The Welsh mountains may lack the raw altitude of Alpine peaks, but compensate with unrelenting terrain underfoot and weather that shifts without warning.
78K
The route departs Llanberis and moves through the Glyderau range before continuing across the rugged landscape that defines this corner of North Wales. Runners encounter sustained climbs on rocky trails, exposed sections where weather can change rapidly, and technical descents that demand concentration late in the race. The course includes multiple mountain passes and ridgeline sections, with terrain ranging from well-worn footpaths to loose scree and boulderfields that require picking careful lines at pace.
100K
The route departs Llanberis and ventures deep into Snowdonia's core mountain ranges, utilizing a mix of rocky mountain paths, ridge traverses, and technical singletrack. Runners encounter the full character of Welsh mountain terrain: steep rocky climbs, technical descents requiring careful foot placement, and exposed sections where weather exposure becomes a factor in race strategy. The course includes significant night running, with most finishers completing the distance across two nightfall periods. Navigation demands increase after dark, making headlamp skills and the ability to read terrain in limited visibility critical to forward progress. Aid stations provide strategic resupply points, but self-sufficiency between stations remains important given the remote nature of much of the route.
163K
The route travels clockwise from Llanberis, moving through the Glyderau range before dropping into the Ogwen Valley. From there, runners head south through the Carneddau mountains and into more remote terrain around the Moelwynion range. The return leg passes through the dramatic landscapes near Beddgelert before the final push back to Llanberis through the shadow of Snowdon itself. Aid stations are spaced to accommodate mountain logistics rather than runner convenience, with some sections requiring sustained self-sufficiency between support points.