The ERENO 20K is the short course of the Puerto Vallarta by UTMB®, a 20km trail race with 1,050m of elevation gain held annually in Mexico as part of the UTMB World Series. I ran my first UTMB trail race there in April 2026. Here's what I learned—and what you need to know before you sign up.
What is ERENO by UTMB?
The ERENO 20K is one of the five distances offered by Puerto Vallarta by UTMB®, the only Latin American stop on the UTMB World Series circuit. The race covers 20 km with 1,050 m of elevation gain, between the Sierra Madre Occidental and the Mexican Pacific coast, finishing on the Malecón in Puerto Vallarta. Each finisher receives 1 Running Stone, the entry currency for the UTMB World Finals lottery in Chamonix.
In 2026, the event brought together more than 1,800 runners from 45 countries over the weekend of April 16-18.
My story: when trail running forces you to change your goal
Kilometers 0 to 7: The Race I'd Imagined
The race started exactly as I'd envisioned. Good legs. Good sensations. The machine—that good old diesel engine—was ramping up.
Then at kilometer 7, on the first technical descent, the adrenaline pushed me to go for it and keep up with the 37K runners who had just joined us on the trail. I gave it too much, at a point where I should have been content to hold back…
Crack. Sprained ankle.
The Moment Everything Changed
From that moment on, everything changed. It was no longer a race about performance. It had become a race of character. Electric shocks with every step. Dozens of runners passed me. Frustration. Anger at myself.
After a few minutes where all my thoughts were swirling in my head, I managed to get going again, limping, and finish that damn descent somehow.
The 600m Elevation Gain: Re-engagement
This is when the biggest challenge of the race arrives: a steep 600m elevation gain.
Paradoxically, this is where I find my motivation again. Climbing on tiptoe is less painful, so I keep going. New goal: to finish.
At the next aid station: ankle massaged and strapped, two Advil, three peanuts, and I'm off again. The pastis will have to wait.
The Finish Line: Pride Before the Clock
There was still a whole mountain to descend, but the pain gradually fades and becomes bearable. At the finish line, it's no longer about ranking, only the pride of having made it to the end.
3 lessons of a first UTMB trail race
- Humility — The technical terrain doesn't forgive over-enthusiasm. Holding back on the first descents isn't optional, it's essential.
- Patience — A race is rarely won where you expect it to be. Accepting the need to revise your objective mid-race is a skill in itself.
- Resilience — Finishing injured teaches you more than arriving fresh. Trail running rewards those who stay on their feet, not those who start fast.
First trail running lesson. First UTMB trail race. Certainly not the last.
Puerto Vallarta Trail by UTMB:
Discover all the details of your running trip to Puerto Vallarta: program, accommodation, support, etc...
ERENO by UTMB Puerto Vallarta : practical information
| Race | Details |
|---|---|
| Distance | 20 km |
| Elevation Gain | 1 050 m |
| Start Location | Canopy River Park, Puerto Vallarta (Jalisco, Mexique) |
| Finish | Malecón de Puerto Vallarta |
| Start Time | 6:30 AM (Saturday) |
| UTMB Index | Yes — 1 Running Stone |
| Required Skill Level | Intermediate to advanced runner, comfortable on technical descents |
| 2027 Edition | First week of March (event date changed) |
| Official Website | puerto-vallarta.utmb.world |
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