The Scale of Trail

The 2027 London Marathon will run across two days. Elite women on one day and elite men the other, with 100,000 runners total across the two races. London Marathon Events (LME) is calling it a "once-in-a-generation, one-time-only" event. Hugh Brasher, who runs LME, says it will be "one and done."

I have a hard time believing that.

1.33 million people entered the lottery for 2027. The year before, 1.13M applications, up 36% YOY and nearly doubled from 2024. Adding a second day will roughly double how many people get in to what is already one of the largest marathons on the planet…and it lets LME collect another day of entry fees. Brasher is projecting more than £150 million for charity and £400 million in economic benefit off the back of the bigger event. That's significant, given that the event is already one of the biggest charity events in the world.

One-offs that print money tend not to stay one-offs. I don't think that demand is going to suddenly evaporate, and if London pulls this off without the city completely locking up, every other marathon Major is going to run the same math.

The venue for a road marathon is typically a large city. Closed roads, massive hotel inventory, and infrastructure and transit systems designed for huge amounts of people. Yes, they're expensive to run and can be a headache for both visitors and residents, but the growth has an elastic quality. Cities can absorb a lot of visitation (or in this case, add an extra day).

That type of growth is exciting for road. But now try to picture the trail running version of “adding a day”. I don’t think it works.

There's been a lot of talk about the growth of trail running, why that matters, and how it manifests through retail, racing, and different geographies. There is, rightfully, a lot of excitement about that growth. More than 50 million Americans ran or jogged in 2024, and 16.1 million of them ran trails. Trail has grown around 8% annually over the last 5 years. More people running on dirt means healthier people, opportunities for outdoor gear brands, and hopefully more people who are connected to the public lands they’re often running on. We're coming off the back of the Broken Arrow/TrailCon/Western States weekends, one of the busiest of the year. But how do you continue to grow the competition side of a sport that with signficant barriers to both participation and competition?

Take Western States, one of the most prestigious ultra races in the world, which happened over the weekend. The field is capped at exactly 369 runners. Not because that's what the demand supports, but because that number is a condition of the race's existence. The course runs through the Granite Chief Wilderness, and when Congress designated that wilderness in 1984, the race got grandfathered in on one condition: it could never start more runners than it did that year. That year there were 369. Meanwhile, lottery entries for races like Western States, Hardrock, Leadville, Wasatch, UTMB (the list goes on) continue to grow.

Western States is the extreme case, but it isn't an outlier in kind. Nearly every significant trail race in the US runs on public land under special use permits, and those permits cap capacity. Hardrock is capped at around 146 runners by its Forest Service and BLM permits. Nearly 3,000 people applied for those spots in 2026. And it's not an American quirk. In the Black Forest, the new Freiburg Trailrun has a 100K on its roadmap that may never happen; the organizers say it depends on conservation approvals and permits.

Those numbers do brutal things to the math of putting on a race. A road marathon spreads costs across tens of thousands of entry fees and huge corporate sponsors. A 100-miler divides remote aid stations, medical coverage, insurance, and permit compliance across (maybe) a few hundred. So, that gap ends up getting filled with ever-rising entry fees and a dependency on sponsors. Races manage to be constantly oversubscribed and financially fragile at the same time.

Trail running has largely attempted to satisfy demand by adding races. The UTMB World Series is probably the clearest (and often most controversial) case; they're up to over 60 events across five continents now, with over 130k participants in 2024. Circuits are expanding, more independent ultras are getting started, and new formats like Backyard Ultra have surged in popularity.

But I think that inventory can still feel thin. The average ultra event in the US runs small: 100-milers average just over 100 finishers, 6-hour timed events average 22. There are local 10K and 25K trail races, but nothing at the scale of the road 5K or half. The extensive on-ramp from local 5k to ticking off marathon majors that turns road running into a massive culture doesn’t quite work for trail. How many 100-person ultras can you realistically add?

Part of the answer comes down to what makes a race possible in the first place. With smaller fields, the math on entry fees makes it harder to run events; races need $$$ from sponsors, and sponsors pay for visibility. The Majors can sell that visibility because they have something trail doesn't: a clear broadcast product.

London puts roughly 750,000 spectators on the streets, had around 3 million TV viewers, and added more than 47 million views across BBC Sport's social channels in the days after. Add the charity storylines and human interest features and you get a full week of national attention around a single Sunday morning. Those numbers are why Brasher can project £150 million for charity and £400 million in economic impact. Sponsors aren't just buying a logo at the finish line; they're buying everything around it.

Trail can't produce attention at that scale in any format. The races happen hours from the nearest city, across terrain spectators mostly can't reach, over durations that don't quite align with an afternoon at the pub. Livestreams are brutal to make: camera operators on e-bikes chasing runners through terrain with no road access, satellite uplinks in dead zones, coverage windows measured in hours or days, and long stretches of dead air where the stream is just watching an aid station. There aren't many teams with technical broadcast experience, especially in the US. Broken Arrow streamed all three of its races on Nike's own YouTube channel this year, drawing viewers somewhere between 25k and 40k by some estimations. But a YouTube "view" can mean a lot of things, so even that number might be flattering. Beyond streams, the visibility is in social clips, a few articles about winners in outdoor publications, and podcast recaps, which mostly reach people who were already fans.

Brands and organizers are currently paying in the hope that the visibility is valuable (and helps them sell shoes). Maybe it is. It works great for UTMB week (UTMB claims 15.8 million livestream viewers across its 2024 season, a self-reported number doing a lot of work), but outside of that, I think the value of livestreams is a harder sell and the watchers more sporadic. More esoteric marketing expenses tend to get cut when the ROI isn't there. And a race that can't grow its field can't grow into better unit economics, so that sponsor money isn't just funding cameras. It's propping up the whole professionalized layer of the sport.

Funnel or no funnel, I'm skeptical trail can scale the way road running has scaled. And honestly? That might be fine.

Maybe trail running doesn't become a bigger “sport” in terms of racing (both pro and amateur). It just continues to grow as a category. More people in trail shoes, more gear sold, a small competitive scene at the top with a media footprint out of proportion to its size, and a long tail of people running dirt roads or jogging part of a hike without ever entering a lottery. That's not a failure. It might be the healthiest version of the sport. The same caps that make the business hard are what keep a Hardrock start line feeling like a Hardrock start line, and I doubt anybody who gets into Western States wishes there were a few thousand other people on the trail.

Right now, the growth at the top of trail is going to be constantly increasing entry fees and new articles about record lottery entries every year. The growth at the bottom is going to be trail running shoes, on both casual hikers and competitive runners. What the middle looks like over the next 5 years is anyone’s guess.