It's UTMB week, featuring one of ultra trail running's most iconic events

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This week there is only one story in the trail running world, and that’s the Ultra-Trail Mont-Blanc finals in the French ski resort of Chamonix. There are actually a bunch of races that make up UTMB week, but without doubt the big one is the 100-mile circumnavigation of Mont Blanc, known simply as UTMB.

This is perhaps the highest profile trail race in the world, attracting the best pros and thousands of enthusiastic amateurs. It’s a monster - this year it’s 174k with 10,000 metres of elevation. The race takes runners through three countries - France, Italy and Switzerland.

In terms of atmosphere, it’s a race like no other. The crowds are insane, and for them, spectating is its own kind of participation sport. It’s a real spectacle.

There is also great live coverage of race week from Chamonix in terms of live athlete tracking and live video streaming, and it starts in earnest at 6:15pm AEST today (Thursday) with coverage of the OCC event.

Live coverage of the CCC starts at 5pm on Friday and the big one, UTMB, kicks off at 1:45am on Saturday. If you’re looking for someone to follow at UTMB, I spoke to Brisbane runner Amber Wood about her road to Chamonix. She’s in bib 1388 and you can follow her progress live from the early hours of Saturday.

What, exactly, is UTMB?

It’s a good question, because it’s quite confusing. UTMB - Ultra-Trail Mont-Blanc - is the name given to this blue ribbon 100 mile race. But these days it’s much more than that.

UTMB, the race, is the culmination of the UTMB World Series, which consists of more than 50 races around the world. Four of these 50 races are designated as “majors”, one each from North America, Asia, Europe and Oceania. And the UTMB race itself stands alone as the UTMB World Series final in the 100 mile distance.

UTMB is not the only race in UTMB finals week - there are also finals over the 50k and 100k distances - the OCC and CCC respectively.

So while UTMB, CCC and OCC are the three UTMB World Series Finals races, there are also other races run during UTMB week. The PTL is a 300k race for teams of two or three. The TDS is a 148k race, the MCC is 40k and the ETC is 15k. There are also races for younger runners. So it’s a full on festival of trails.

Adding to the confusion is the fact all 50-plus events in the UTMB World Series are labelled UTMB events. In Australia there are two - Ultra-Trail Australia by UTMB and Ultra-Trail Kosciuszko by UTMB.

So, to summarise (don’t worry, there’s no exam at the end):

• There are 50-plus UTMB World Series races around the world

• Each of these carries some kind of UTMB branding, for example Tarawera Ultra-Trail New Zealand by UTMB (the one exception is Western States which stands alone as a trail running brand in and of itself)

• Four of these are World Series Majors - the Oceania version is Ultra-Trail Australia by UTMB

• The series culminates in the “world series finals” which includes OCC over 50k, CCC over 100k and UTMB over 100 miles

If this all sounds a bit commercial, that’s because it is. The UTMB organisation is slick and professional. The website is impressive - including fantastic live coverage on race day - and they produce a range of videos that promote the events and the athletes really well.

There is definite up-side to all of this - in some senses UTMB is essentially “professionalising” the sport of ultra-running. That’s not to say other events aren’t run in a professional way - they are - but the UTMB machine is taking that to a whole new level.

There are plenty of people who think this is a good thing and fundamental to growing the sport, especially at the elite level. After all, if people are going to be making a living as professional trail runners, the events themselves need to measure up.

But there are just as many who worry a little that in becoming more “professional”, the sport risks losing its soul.

From my perspective, I hope there is room for both. For events that seek to elevate themselves onto a higher plane and those that retain their local, “let’s just get out and run some trails” ethos.

There’s no doubt the sport is booming with races invariably selling out. It will be interesting to see over the next decade how these big events evolve.

What makes this race so special?

There are a range of things that make UTMB a key race in the annual trail running calendar. First and foremost for me is the spectacular scenery. We simply don’t have courses like this in Australia, traversing such impressive mountainous terrain.

I’ve never been to Chamonix, but the video footage of the race is breathtaking. I can only imagine what it must be like to run in such beautiful surroundings.

Then there is the atmosphere. The crowds at the start and finish are incredible. And along different parts of the route there are people cheering runners on, with cowbells ubiquitous.

It’s also a brutally difficult course, so it’s a massive test of endurance (the 46 hour 30 minute cut-off time is indicative of just how tough it is). And it generally draws a stellar field. It’s not every race where you get to line up with the world’s best.

The course

Probably the most notable characteristic of the UTMB course is how steep the climbs are. Obviously it’s in the high mountains, so that shouldn’t be a surprise, but the climbs here are precipitous - and so are the descents.

It’s those high mountains that give the race its amazing views, but the gradient is hard on the legs. The descents in particular tend to shred quads. Even an experienced runner like Australia’s own Lucy Bartholomew has been caught out by this.

She says her quads were in such bad shape last year that she was forced to walk all the descents in the second half of the race. And she still finished in the top 10 women.

Some rock falls have meant diversions to the course so this year it’s stretched out beyond the usual 170k to 174k.

Five-time UTMB runner Sally McRae offered some insights into the course in the official preview posted by the Freetrail podcast, hosted by pro runner Dylan Bowman.

“There actually are long, runnable sections,” McRae says. One of those is the first 20 miles. This is a classic trap for runners who are already full of adrenaline and who are feeding off the energy of the crowds, who line this first part of the course to cheer the competitors on.

It’s also crowded on the course and the temptation is to nip past a runner here, duck past another there. And all of a sudden, you’ve gone out too fast. “The first 20 miles can destroy your race. It’s fast, then a steep climb, a change of weather - and if you are not taking care of yourself pacing, it’s going to be a rough time getting to Courmayeur,” McRae says.

Another complication for runners is the fact there is only one location where you can collect a drop bag, and that’s at the 83k mark when you reach Courmayeur, the Italian Alpine resort. That means runners need to carry everything they may need for that first 83k, most notably their nutrition.

There is, of course, food available at the numerous aid stations around the course. But it’s not the grab and go, chips and lollies we’re used to here. Instead, it’s baguettes and cheese, cured meats and soup. More charcuterie board than kid’s party food. Probably not an option for everyone.

So, starting conservatively is important, as is nailing your nutrition. Sound advice for any ultra, but perhaps more so than ever here because the final third of the race is punishing. That’s at least in part because of the damage done to your quads with so much descent in the preceding 100k.

McRae puts it like this: “When you have that much descent, it really beats up your body. The last 50k … is probably one of the most soul-crushing parts of any race I’ve ever done in my life.

“It’s six miles up, six miles down, six up, six down. You do that three times in a row. The last one has six false summits before you get to the top.” Sounds like fun.

The 5:45pm start time is another curve ball for runners. It’s around dinner time, making pre-race nutrition difficult to judge. “You’re too nervous to sleep so you’re laying in bed, looking at the clock. But that’s also the time the weather turns… that’s when storms come in,” McRae says.

The evening start means that, apart from the elite field, everyone has to spend two nights on the course, adding a layer of complexity to an already demanding event.

What to expect

Firstly, it looks like the weather forecast for the weekend in the Chamonix region is not great with rain likely. This is not all bad - it should keep the overnight temperatures up a little. But if it rains too much, thousands of sets of feet on those trails might churn things up and make for tough and muddy going at the back of the pack.

On the women’s side of the field, Courtney Dauwalter is back looking for her fourth title having won the race in 2019, 2021 and 2023. It’s hard to mount any argument against Dauwalter being among the greatest ultra runners of all time.

She’ll be pushing to try to win back the course record she set in 2021 and which was broken by fellow American Katie Schide last year. That record stands at 22 hours 9 minutes.

Unfortunately for ultra fans, Schide is focused on the World Mountain and Trail Running Championships in late September so won’t be lining up at UTMB. A Dauwalter-Schide showdown would be a race for the ages.

Kiwi Ruth Croft is another big chance. She was second to Schide last year and is a consistent performer at the sharp end of the big races. She’s at home on the course, having won the 50k OCC and 100k CCC in the past. She’s aiming to be the first woman to win all three UTMB finals races.

Abby Hall, another American, is also fancied. She won Western States at the end of June, so there are questions about whether she can back up for another really tough test so quickly. Hall also won the Ultra-Trail Kosciuszko last November.

Also worth watching will be Bartholomew, partly because she’s an Australian, but also because she’s in really good shape going into this race. She was 10th last year and I wouldn’t be at all surprised to see her better that this time around.

While there are definite favourites in the women’s race, the men’s field is wide open. One of the most interesting runners is Francois D’Haene, a four-time champion who last won the race in 2021.

If he can make it five here it would be an amazing story. He turns 40 in December and suffered a broken ankle that required surgery in 2022. But he’s back in form having won the Transylvania 100k race in May.

Another Frenchman, Ludo Pommeret, is also in the veteran class having turned 50. But he is also coming into the race in form having won the Hardrock 100 mile race in record time. That race was just seven weeks ago, but Pommeret also won Hardrock in 2024 and backed up to be fifth at UTMB. He’s a real contender.

Brit Tom Evans, Americans Hayden Hawks and Jon Albon and Kiwi Dan Jones are probably the best of the rest.

The elite end of the field will be done and dusted within 24 hours. But for hundreds of others this race is a once in a lifetime experience. They have 46.5 hours to complete the 174k.

The emotion as people run through the crowd-lined streets of the French ski resort and cross the line is quite something to behold. And that combination of a super challenging course, incredible and vocal support and the emotional release after what is frankly an astonishing physical and mental achievement is what really makes this event a one of a kind.

I can’t wait to see it unfold.