How far is the Snowdonia Trail Marathon Eryri?

The Snowdonia Trail Marathon Eryri offers 4 distances: 10K (6.2 miles), Half Marathon (21.2 km / 13.2 miles), Marathon (43.8 km / 27.2 miles), Ultra Marathon (56.0 km / 34.8 miles).

How much climbing is in the Snowdonia Trail Marathon Eryri?

The 10K has 374 m of ascent. The Half Marathon has 1,225 m of ascent. The Ultra Marathon has 2,300 m of ascent. No figure yet for the Marathon.

How hard is the Snowdonia Trail Marathon Eryri?

10K: Hard. Half Marathon: Very Hard. TRP grades come from distance and climb measured off the course file, not from the organiser. The Marathon or Ultra Marathon isn't graded yet.

Is the Snowdonia Trail Marathon Eryri course marked?

Yes, the course is marked. Navigation skills are not required.

When is the next Snowdonia Trail Marathon Eryri?

Sat, 10 Jul 2027. Entries open.

Always Aim High Events Snowdonia Trail Marathon Eryri

Llanberis, GwyneddSat, 10 Jul – Sun, 11 Jul 2027

Ten kilometres to fifty-six from Llanberis, under Yr Wyddfa, with the marathon and ultra both ITRA and UTMB indexed.

Distance	Ascent	Per km
56 km Ultra Marathon	2,300 m	41 m
43.8 km Marathon	—	—
21.2 km Half Marathon	1,225 m	58 m
10K	374 m	38 m

mountainMarked course

Nobody has reviewed this one yet

No reviews of the Snowdonia Trail Marathon Eryri, and nothing on what people wore. Both are things no organiser publishes and every runner wants before they enter — how it actually went, and what was on your feet.

Ran it? Write the first review

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HARD

TRP grade · E2·T3

Start time not confirmed yet — check with the organiser.

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Train for it: routes near the start

Routes starting within 20 km of Llanberis, Gwynedd, nearest first. Each one has a free GPX file and a TRP grade, so you can rehearse the ground before race day.

EXPERT

Snowdon, Grib Goch, Glyder Fawr, Y Garn & Elidir Fawr from Llanberis Trail Running Route

29.1km · 2,306m climb · Loop · 0.2km away

Crib Goch is one of the most exposed ridges in Britain, and this route puts it in the middle of a big mountain day rather than as the whole objective, so you get the scramble and a proper crossing into the Glyderau either side of it.

Checked Jul 2026

VERY HARD

Yr Wyddfa via Llanberis Path

16.2km · 959m climb · Out & back · 0.2km away

It's the most runnable line to the summit of Yr Wyddfa, following the rack railway most of the way up, so you can move fast on genuinely good underfoot conditions rather than picking through rock.

EXPERT

Yr Wyddfa via Miners' Track, Pyg Track and Crib Goch

12.0km · 710m climb · Loop · 8.5km away

Most people treat the Miners' and Pyg Tracks as a straightforward there-and-back pairing, but this GPX shows the loop actually crossing Crib Goch, which changes the entire character of the day.

All Eryri (Snowdonia) routes →

How to enter

Sat, 10 Jul – Sun, 11 Jul 2027 · Entries open

Enter on their website ↗

Entries are handled by Always Aim High, not by us. We take nothing for sending you there.

Add to your calendar · as an all-day entry, until the start time is confirmed

Common questions

: The Snowdonia Trail Marathon Eryri offers 4 distances: 10K (6.2 miles), Half Marathon (21.2 km / 13.2 miles), Marathon (43.8 km / 27.2 miles), Ultra Marathon (56.0 km / 34.8 miles).
: The 10K has 374 m of ascent. The Half Marathon has 1,225 m of ascent. The Ultra Marathon has 2,300 m of ascent. No figure yet for the Marathon.
: 10K: Hard. Half Marathon: Very Hard. TRP grades come from distance and climb measured off the course file, not from the organiser. The Marathon or Ultra Marathon isn't graded yet.
: Yes, the course is marked. Navigation skills are not required.
: We don't hold a compulsory kit list for the Snowdonia Trail Marathon Eryri. Always Aim High Events confirm mandatory kit in their race information, usually in the final instructions.
: We don't hold published time limits for the Snowdonia Trail Marathon Eryri. If Always Aim High Events set cut-offs, they'll be in the race information.
: We don't hold a checkpoint list for the Snowdonia Trail Marathon Eryri. What's on the table varies a lot between races, so check the Always Aim High Events race information rather than turning up expecting food.
: Not yet — we don't hold a course file for the Snowdonia Trail Marathon Eryri. Some organisers only send the GPX to entrants. If we get one, it goes up free, with no sign-up.
: Sat, 10 Jul 2027. Entries open.