Trail Running  | XTERRA Snowdonia Trail Marathon Eryri 2025

XTERRA Snowdonia Trail Marathon Eryri 2025 Trail Running Ultra Marathon

The Snowdonia Ultra Trail Marathon Eryri encompasses 2199m of climbing over 57km. This beautiful route shares the same start as the marathon, leaving Llanberis via Maes Gwm, before descending into Nant-y-Betws, with stunning views over Llyn Cwellyn and Beddgelert Forest. The Ultra breaks off through the forest to visit the beautiful Cwm Tresgl and Cwm Pennant, before rejoining the Marathon Route in Nant Gwynant to ascend the slopes of Yr Wyddfa (Snowdon). Finally, you are rewarded with a 7km descent to a heroes' welcome back at the Event Village in Llanberis!

The Ultra Marathon is a UTMB Indexed race and will earn finishers 3 ITRA points.


13 Jul 2025




Route Description

The Ultra Trail Marathon route leaves Llanberis via an ascent of Maesgwm with continued views of Yr Wyddfa (Snowdon), before dropping down towards Rhyd Ddu. Upon reaching Beddgelert Forest the Ultra route breaks away from the Marathon route to explore the beautiful Cwm Tresgl and Cwm Pennant. Rejoining the Marathon Route, the Ultra works its way along Afon Glaslyn and Llyn Gwynant to the slopes of Yr Wyddfa, to the Finger Stone via the PyG track. Once at the Finger Stone runners will descend by the Llanberis Path all the way to the finish line. This route is a trail running enthusiast's paradise; with mountain, forest, stone path, slate quarries and tracks it isn’t hard to keep motivated the whole way around.


Tier 1 Price

Ends: 11/08/2024

  • £89.99

Tier 2 Price

Ends: 31/01/2025

  • £94.99

Tier 3 Price

Ends: 06/07/2025

  • £99.99

Tier 4 Price

Ends: 10/07/2025

  • £104.99

Important Information

Minimum Age


Start Time

Cut Off Times

Aid Stations


Mandatory Kit

Are you in?

See Start List

Final Instructions

Will be sent out and available to download 1 week before the event.

We are proud that all our events are bilingual. Signs, registration and commentary are available in English and Welsh.

Event Partners XTERRA Snowdonia Trail Marathon Eryri 2025

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