Eryri 100M

Eryri 100M

It is the organiser’s grand tour of Eryri, starting and finishing in Llanberis. The route crosses Yr Wyddfa, the highest peak in Wales, passes Llyn Gwynant and Llyn Idwal, and goes through Capel Curig, Dolwyddelan, Blaenau Ffestiniog, Croesor, Beddgelert, Rhyd Ddu and Betws Garmon. Expect technical trail and exposed ridges, rocky scree, boulder-strewn paths, boggy moorland and glacial valleys, with the slate industry’s remains along the way.

Larger aid stations serve hot food and drinks; the race page does not publish aid-station distances or intermediate cut-offs. The race is semi-autonomous, with personal assistance only at designated points, and the mandatory kit is checked at random at bib collection, at the start and at selected aid stations. The organiser advises planning for device battery life and having a crew and a driver home afterwards.

This page covers the 2027 edition. A 14:00 Friday start and up to 48 hours means at least one night in the mountains, and possibly two. If the runner shares their own Livebib link, family and friends see the position on the course line, distance covered and a finish estimate that updates as the race goes. Where the phone loses signal, the position is carried forward along the course and marked as estimated, never shown as measured.