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Ultra-Trail Snowdonia by UTMB: Recap and Race Guide (2024)

Published on: 06/22/2023

“Beautiful beyond belief, savage beyond reason.” This is the way the Ultra-Trail Snowdonia (UTS) suite of races introduced themselves to the world in 2018. The race has seen a number of course changes and adaptations throughout the years, all with the aim of becoming a “UTMB of the UK.” And 2023 was the year the UTS truly came together.

Offering countless stunning trails, difficulty levels beyond most UTMB World Series (1) events, a mix of technical mountain trails, ridges, and runnable grassy slopes, and an unexpectedly clear, sunny weekend, UTS 2023 definitely made some waves.

Read on to find out how the 2023 edition of Ultra-Trail Snowdonia by UTMB (2) unfolded and to get an overview of the key races of the weekend for when you’re planning your next event.

Introducing Ultra-Trail Snowdonia by UTMB

runner on Ultra Trail Snowdonia by UTMB
📷©️ @smamaj on Instagram

The first UTS event kicked off in spring 2018 under the watchful eye of Race Director Michael Jones and a handful of well-meaning volunteers from the Welsh valleys. With humble race headquarters at the Heights pub and bunkhouse in Llanberis, it was made up of two events. First, a 100-mile race that began on Friday evening, and then a 50-mile race on the following Saturday morning. The routes included vertigo-inducing ridge running, some serious climbing and descending, and countless bogs to navigate across.

The outcome was worthy of the “savage beyond belief” tagline. There were only 13 finishers out of 46 entrants in the 100 miles. The 50-milers fared slightly better, with 129 finishing (from 166). This was likely because of the much better weather. Indeed, the Friday night had been a continuous downpour on top of the difficult course. Also, the checkpoint cut-offs were aligned with the 100-miler runners, so they had a more generous timeline. And so, a legend was born…

Affiliation with the UTMB Group

Ultra Trail Snowdonia by UTMB start line
📷©️ @sportograf on Instagram

As of 2022 (3), UTS became part of the UTMB group of affiliated races, entering the newly created UTMB World Series. This was Race Director Michael Jones’ dream all along. Indeed, he initially looked to create a mountain endurance running race in the UK that mirrored the main event in Chamonix, France.

Membership in the UTMB World Series means that the races during Ultra Trail Snowdonia weekend offer up Running Stones (4) to participants. This allows them to also gain a UTMB Index for each distance. As a result, it’s the only UK-based set of races where UTMB hopefuls can boost their profile and tick off the pre-requisites to apply for one of the UTMB Series Finals in Chamonix.

This partnership also means an increase in visibility on the world stage. In future years, we can expect Ultra Trail Snowdonia to see ever more international participants – especially those looking for several technical mountain trails to spice up their racing calendar.

History of the Races

Since that now legendary 2018 debut, UTS has gone through a few iterations, always keeping a good number of technical trails on courses passing through the Welsh mythical landscapes. Originally, it was believed that the Welsh name for Snowdonia national park – “Eryri” – meant “land of the eagles.” Although it’s since been corrected to “highlands,” this doesn’t make the location of UTS any less spectacular. Since 2018, participants have not only summited Snowdon (Welsh name Yr Wyddfa). Other highlights include the knife edge of Nantlle Ridge, the fantastic rocky outline of Tryfan, and the difficult Crib Goch. Not only that, participants also got to discover the mining history of the area.

Tryfan, Ogwen Valley, Snowdonia, Wales, UK
Tryfan, Ogwen Valley, Snowdonia

Today, each race takes in epic views of Northern Snowdonia. However, the routes are slightly less difficult than the first editions. Made to be a bit more runnable, some of the courses are on similar trails, while some are completely new. The start location has also moved a few times, with the more recent HQ at the National Slate Museum (5). This allows the race to accommodate more runners and to offer a few extra facilities for finishers.

Overall, however, some of the defining characteristics of UTS remain: “savage” levels of elevation gain, beautiful views, amazing atmosphere, and technical trails that make this a truly Alpine scale mountain ultrarunning event.

Key facts

As of 2023, the UTS events are set to remain unchanged for the next edition. All of them start and end at the National Slate Museum in Llanberis, covering circular routes.

Here’s a fact sheet for every race of Ultra Trail Snowdonia:

UTS 100 Miles

  • Starts on Friday afternoon (2023 start time was 1pm), max finishing time 48 hours
  • The ultimate grand tour of Snowdonia National Park for those with good trail and ultra running experience and a high degree of self-sufficiency
  • Full alpine scale mountain ultrarunning event with technical trails, lots of climbing, exposure on technical ridges and breathtaking views
  • 168 km with 9500 metres of elevation gain
  • Live tracking with GPS trackers for each participant
  • Outside assistance allowed at a number of aid stations (one person per runner)
  • 4 Running Stones

UTS 100 km

  • Start time: 5am on Saturday morning
  • Max finishing time: 32 hours
  • 103 km with 6400 metres of ascent
  • Features technical ridges, stunning views from some of the most difficult summits in Wales, and a little bit of runnable trails
  • Live tracking with GPS trackers for participants
  • Checkpoints with outside assistance available
  • 3 Running Stones

UTS 50 km

  • Start time: 8am on Saturday morning
  • Max finishing time: 14 hours
  • 55 km with 3300 metres of ascent
  • A so-called “perfect stepping stone into Alpine scale mountain ultrarunning” – difficult under foot, with severe climbing, steep descents, a little bit of ridge exposure, and some runnable terrain
  • No GPS tracker, only timed by arrival at checkpoints
  • No outside assistance allowed
  • 2 Running Stones

UTS 25 km

  • Start time: 10am on Saturday morning
  • Max finishing time: 5.5 hours
  • 25 km with 1300 metres of climbing
  • A “fast and furious” climb up Snowdon followed by a technical descent and another small climb and descent back to Llanberis – a lung buster!
  • No GPS tracker and no outside assistance
  • 1 Running Stone

UTS 2023 Overview

2023 was by far the biggest year for UTS: over 2800 participants were recorded to have registered on the website, representing 64 nationalities. Competitors were expected at registration from the Friday, with the peak of activity taking place on Saturday, when 3 of the 4 events would start.

Although UTS is nowhere near at the level of big European races like the UTMB itself, the UK’s event was still impressive and exciting. It brought together some top competitors seeking to confirm their participation to UTMB in August, as well as lots of first-timers into the world of mountain running.

The race experience – UTS50

The 50k seemed by far the most popular event, attracting not just the highest ranked UTMB pro runner (the UK’s Tom Evans), but also the highest number of registrations (1128 starters). It was certainly a bigger affair than my first experience of UTS in 2018!


We set off relatively fast up the Llanberis path, poles in hand for the first climb of the day. Taking in fantastic views as we climbed to the “finger stone” Bwlch Glas just short of the summit, we were then rewarded with a fun, but technical, descent to Pen y Pass, the crossroads of many trails throughout the weekend. I knew there was a water fountain here so stopped and filled up, which was a great decision since the unexpected heat made us all slow down more than we’d expected by the time we reached the first of the aid stations at Gwastadannas Farm (15.3 km into the run).

Pen-y-Pass from Crib Goch, Snowdonia National Park
Pen-y-Pass from Crib Goch, Snowdonia National Park – ©️ Wikimedia Commons

The decision to carry 3 500 ml soft flasks for fluid proved to be one of the best I’ve made. From this point, the route took us through swampy fields, beautiful forest trails, and up the south side of Snowdon. The south ridge scramble was also on the menu, making the 1000m + climb slow and steady, even more so in the heat. There’s no shade for most of this climb, either, so without extra supplies, many people would miss the time cut-off after descending Snowdon.

Snowdon/Yr Wyddfa

It was a slow, but steady slog up to the summit of Yr Wyddfa, which by this time of the day was full of tourists who’d come to visit the highest peak in England and Wales. Navigating quickly through throngs of children and families, next was the long descent, partly down a rocky path, partly across farmland, to Bron-y-Fedw Uchaf Farm.

Yr Wyddfa, Snowdonia National Park
Yr Wyddfa ©️ Snowdonia National Park

This second checkpoint is the first one where 50k competitors can eat and refill their food supplies, so it’s really busy. All of us were grateful to see bags of salty potato chips and cheese sandwiches – a sign of how dehydrated everyone was!

From here, the following two climbs are more forgiving, but will still test any runner’s abilities after what’s already been a long day. Crossing another set of forest trails before heading up Mynydd Mawr, we were rewarded with some epic views of the route we’d covered behind us. Then it was a quick descent to the final aid station at Betws Garmon before a final push up steep but grassy Moel Eilio.


You can see Llanberis below you as you make your way over this last bump – a massive boost, but there are still over 9km to go once you clear the summit! The first part of the descent towards the Llanberis Path is very steep and tough for the end of an ultra marathon. However, once I reached the gentle downhill gravel track that takes us down to the town, it was easy running to the fantastic finish line. 880 finishers from 1128 starters – not the easiest first ultra for many, but a rewarding, epic adventure on countless stunning trails!

Llanberis Path
Llanberis Path ©️ Snowdonia National Park

Recap of UTS 2023

So, how did the weekend unfold for those at the front of the peloton? The 50k featured one of the biggest names – team Adidas’ Tom Evans (6), who stormed to the finish in first place in just under 5 and a half hours, followed by France’s Mathieu Delpeuch (Team Brooks) and Norway’s Kristoffer Eftedal (Team Hoka). In the women’s race, Swedish Hoka runner Johanna Gelfgren dominated, followed on the podium by Kirsteen Welch and Fiona Pascall (both UK athletes).

The 100-mile race had the biggest story. After winning the UTS 50k in 2019, then the UTS 100k in 2022, Josh Wade finally triumphed in the 100 miles. He was followed by Gregoire Curmer over 1 hour and 20 minutes later, with David Hedges from the US in third. Emma Stuart took the top spot for the women, coming in 8th overall, followed by American athlete Sabrina Stanley and Claire Bannwarth from France.

winner of 100k Ultra Trail Snowdonia Josh Wade
Josh Wade 📷©️ ultratrailsnowdonia

The 100k race crowned Swiss Jean-Philippe Tschumi and British Lizzie Wraith as its winners, while it was an incredibly fast brand new 25k race where British athletes Kris Jones and Holly Wootten were the victorious.

How to Enter Ultra Trail Snowdonia

Entries for the 2024 edition of Ultra Trail Snowdonia by UTMB opened on May 24, 2023, and will stay open as long as the event doesn’t sell out. While there are no vetting pre-requisites, the organizers do suggest some experience is required depending on what distance you’re looking to race.


For the 100 miles, having a UTMB index in the 100k category is a minimum show of experience, while for the UTS100, it’s one in the 50k category. This means you’ll have completed a minimum distance in a race setting, hopefully acquiring some experience of technical mountain trails and self-sufficiency in an alpine setting.

Practical info

Snowdonia National Park and Llanberis are much smaller than many of the ultra marathon events in the UTMB World Series. There is not as much accommodation available on site and there’s very limited parking, too.

To make sure you get a spot close to the start line, check out the UTS official website (7) suggestions early. We recommend renting a car if you wish to visit more of the area, but be mindful of the limited parking options during the event.

How to prepare for Ultra Trail Snowdonia events

UTS is one of the most challenging set of races in the UTMB World Series calendar. Because it covers more technical mountain trails than most other events, including long portions of off-trail running, it can be a challenge for many runners entering such an event for the first time. It is also an eye opener for those used to the more manicured Alpine trails in mainland Europe!

Additionally, UTS features a lot of vertical gain in each of its events, significantly more per km than in other races. Finally, the UK’s mountainous areas should not be underestimated: many runners taking part in the 2023 edition questioned the extensive list of mandatory kit published ahead of the event. However, although at low altitude, the Welsh and British alpine environment can be just as demanding and tough to navigate as much bigger mountains in other countries.

Here are some key tips on how to structure your training if you plan to run UTS:

  • Add a lot of technical mountain trails to your weekly training – ideally, all your long runs should include a mix of runnable and technical, even scrambling, terrain;
  • Train for climbing and descending. This includes hill training workouts, but also strength and conditioning for the mountains;
  • Practice nutrition and hydration options during your long runs;
  • Don’t rely on your watch or smartphone to guide you to safety when out running. Wales offers very little phone coverage, so train to use a map and compass if needed (the course is well marked, but why take unnecessary risks?).

And here is some advice from finishers of the ultra marathon distances, on how to tackle race day in Snowdonia:

Take it easy at the start

All distances start with the Llanberis Path, which is relatively runnable, but can sap your energy in the ultras.

Refill your water bottles as often as possible on a hot day

Many competitors underestimated their hydration needs on a warm day, only to discover how tough it was to ultimately reach Llanberis again.

Don’t underestimate British mountains

British mountainous areas are low-altitude, but that doesn’t make them less perilous. Take all the mandatory kit (waterproof jacket with hood and taped seams included!) as it can prove helpful for the duration of your race (especially if doing 100k or 100 miles where you may be out at night for a long time). Organizers do conduct spot checks on the route, and you may even find it helpful to take additional kit subject to weather conditions – be ready to adapt.

Be prepared for all conditions

Weather can change a lot since the May date puts UTS on the cusp of winter/spring/summer in the UK. So does the terrain. Be prepared for anything from rocks and boulders, to soft grass, to river crossings and even wading through water at times. Unlike similar trails in Europe, note that a lot of UK trail running is in full nature, sometimes not on marked paths.

Head up and don’t forget to enjoy those epic views

On a sunny day, they’ll make you forget all about the pain in your legs!


UTMB World Series (retrieved on 06/09/2023)

Ultra-Trail Snowdonia by UTMB (retrieved on 06/09/2023)

Ultra-Trail Snowdonia To Be UK’s First UTMB® World Series Trail Running Event
Ultras.Wales (retrieved on 06/09/2023)

About the UTMB World Series
UTMB World (retrieved on 06/09/2023)

National Slate Museum (retrieved on 06/09/2023)

Tom Evans on Instagram (retrieved on 06/09/2023)

Getting to UTS
Ultra-Trail Snowdonia by UTMB (retrieved on 06/09/2023)

Alecsa Stewart

Alecsa Stewart

Alecsa is an ultra runner, mountain guide, and freelance writer living in the Pyrenees-Orientales (France). She is passionate about the mountains and life in the wilderness and also practices cycling, climbing, and skiing from time to time. Her passion is to share her adventures with others and inspire them to spend more time outdoors. She’s completed iconic races like the UTMB Mont-Blanc and Lavaredo Ultra Trail and she’s switching to some road running this year, aiming to complete the Manchester and Berlin Marathons, while also looking to improve her time at the UTMB CCC.

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