The Snowdonia Trail Marathon Eryri is a multi‑distance trail running festival set in the heart of Eryri National Park (Snowdonia), Wales. Organised by Always Aim High Events, it offers a 10 K, Half Marathon, Marathon and Ultra Marathon, all starting and finishing in Llanberis and featuring some of the UK’s most dramatic trail terrain.

Key Details

• Date & Time: Satuday, 10 July and Sunday, 11 July 2027

• Location: Llanberis, Gwynedd, Wales

• Event Types:

  • 10 K (~9.8 km)

  • Half Marathon (~12.9 miles)

  • Marathon (~27.3 miles)

  • Ultra Marathon (~57 km)

Race Description

The routes traverse the varied and spectacular landscapes of the Eryri National Park—featuring mountain ascents, ridgelines, forest tracks and sweeping views of the Welsh countryside. Key sections include trails around Rhyd Ddu, Beddgelert, Nant Gwynant, Pen y Pass and the summit of Yr Wyddfa (Snowdon).The Marathon and Ultra distances are UTMB‑indexed, highlighting the high challenge level.

What’s Included

• Fully marked courses with marshals and support vehicles.

• Event village in Llanberis with food, shopping and live commentary.

• Finisher mementos for all participants.

• Ever‑present bilingual support (English & Welsh), environmental commitment and local community cooperation. 

Additional Information

• Minimum Age: 17 years for Half Marathon.

• Terrain & Elevation: Rugged trail terrain with substantial climbs; for example the Half Marathon has circa 1,192 m of ascent.

• Time Limits & Cut‑offs: Cut‑offs apply for safety; exact times published in Final Instructions.

• Environmental & Local Impact: The organisers implement a zero‑tolerance litter policy and work closely with local communities to minimise disruption.