Wales' Spectacular Mountain Half Marathon

Trail Running | Snowdonia Trail Marathon Eryri 2027

Snowdonia Trail Marathon Eryri 2027 Trail Running Half Marathon

The Snowdonia Trail Half Marathon Eryri is a standout mountain race in its own right, offering an unforgettable trail running experience in the heart of Eryri (Snowdonia) National Park. Starting and finishing in Llanberis, the route combines challenging climbs, fast-flowing trails, and breathtaking scenery beneath the dramatic peaks of North Wales.

This is a race designed for runners who want to experience the beauty and challenge of mountain trail running over the classic half-marathon distance. Expect rugged terrain, panoramic views, and an incredible atmosphere as you take on one of the UK’s most scenic trail half marathons.

From the energy of the event village to the stunning landscapes surrounding Yr Wyddfa (Snowdon), every part of the experience is built to make race day memorable. Whether you’re chasing a competitive finish or simply looking to enjoy an epic day on the trails, the Snowdonia Trail Half Marathon Eryri delivers a challenge worthy of the setting.

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Route Maps
Route Description
Prices
Important Information

Dates

11 Jul 2027

Location

Llanberis

Distances

Half Marathon

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Routes

Snowdonia Trail Marathon Eryri 2022 Mel Parry 22

Run - 13.2 miles

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Route Description

Don't let the distance fool you. The Trail Half Marathon Eryri is a serious mountain running challenge, taking you from the heart of Llanberis high onto the slopes of Yr Wyddfa before returning through the spectacular landscape surrounding the village.

The climbing begins early as runners leave Llanberis and head upwards onto Yr Wyddfa. As the route gains height, the views become increasingly dramatic, with the course reaching the high mountain above Clogwyn Du'r Arddu before beginning its long journey back towards the valley.

From exposed mountain terrain, the character of the race gradually changes as you descend onto quieter trails and tracks beneath Yr Wyddfa. The final kilometres bring you back towards Llanberis, where the mountains that have dominated the race provide the backdrop to the finish.

At approximately 21km with around 1,250m of climbing, this is very much a mountain half-marathon. The revised 2027 course combines a major high-level challenge with a route designed to give the event team greater opportunities to support runners throughout the race.

Big climbs, rugged trails, huge views and a memorable finish in Llanberis make this one of the most rewarding ways to experience trail running in Eryri.

Pricing

Tier 1 Price

Ends: 13/09/2026

£45.99 UK Athletics Affiliated
£47.99 Non-affiliated

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Tier 2 Price

Ends: 31/12/2026

£47.99 UK Athletics Affiliated
£49.99 Non-affiliated

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Tier 3 Price

Ends: 04/07/2027

£49.99 UK Athletics Affiliated
£51.99 Non-affiliated

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Tier 4 Price

Ends: 08/07/2027

£52.99 UK Athletics Affiliated
£54.99 Non-affiliated

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Important Information

Age

You must be at least 17 years old to take part in this race.

Registration

If you opted for a postal entry, there is no need to register in person before the event. Your Final Instructions will be emailed to you, and they will also be available on the website 10 days before the race.

If your bib is not being posted, you will need to collect it from registration. Registration will take place on Saturday afternoon and before the race on Sunday morning. We will confirm specific times in your Final Instructions.

Registration is usually located in the event village in Llanberis, situated next to the Community Centre - LL55 4UR

Start Time

The Half Marathon usually starts at 07:00, though this is subject to change. The race start time will be confirmed in your Final Instructions, which are available to view on the website 10 days before the race.

Cut-Off Times

In the interest of athlete safety and the safety of our volunteers on the course, there will be strict cut-off times in place.

You must reach the feed station at Bron Y fedw (12.5km) in 3 hours and 25 minutes

Finish Line Timing ends after 5hours 15 minutes

Feed Stations

Water will be available on the mountain at 5.75km, and water, High 5 energy drinks and gels at 12.5km.

Please note that our races are cupless, meaning you must provide a reusable race cup or bottle to fill at feed stations. Race cups are available at the event shop in the event village.

Prize giving

We hold a prize-giving ceremony after the racing; approximate timings will be detailed in the Final Instructions. It is a good idea to listen out for information on any updates that come in over the tannoy. Sometimes the ceremony may be delayed, and we wouldn't want you to miss out. We don't send out prizes after the event, so make sure you attend the ceremony and receive your big Welsh cheer!

Prize Categories for the Snowdonia Trail Half Marathon Eryri are (for both men and women)

Overall: Top 3*

Senior: 1st runner

V40: 1st runner

V50: 1st runner

V60: 1st runner

V70: 1st runner

All prizes must be collected on the day.

* If any runner places in Overall and Vet, then a drop-down system will occur.

Compulsory Kit

All competitors must carry the compulsory kit listed below. This kit is for your safety due to the often unpredictable and quickly changing mountain conditions and the isolated nature of the route.

Spot checks will be in place, and anybody found without the required kit will not be allowed to race.

Waterproof jacket and trousers - with taped seams and an integrated attached hood.
Suitable off-road running shoes - trail shoes
Hat/Buff and Gloves (head and hand cover)
Whistle
Emergency food
Foil blanket
Drinking water
Mobile telephone
Reusable race cup or bottle