It’s 11 o’clock in the morning, and a rebel yell is echoing off the canyon walls loud enough to encourage some skittish birds to flee their trees for the safety of the open air. And they’re not the only ones taking flight. All around me and all around this sandstone-ringed valley just outside Jasper, men and women, young and old, are climbing.

They are stuffing whole fists into cracks in the sandstone cliffs. They are stuffing calloused hands into chalk sacks for that extra bit of grip. They are pinching minuscule outcroppings of rock between fingers and thumb. They are clipping rainbow-hued ropes into bolts sunk deep into the rock (or bypassing them entirely). They are hanging upside down. They are costumed. They are bare-chested. They are slipping. They are falling. They are caught midair as their partners lock down the ropes. And every hour on the hour for the next 23 hours, they’ll scream, they’ll hoot and they’ll holler to mark the passage of time.

Welcome to the annual 24 Hours of Horseshoe Hell at Horseshoe Canyon Ranch. This endurance-sport climbing competition sees teams of two compete to climb the most routes and gather the most points during a 24-hour period—10 a.m. to 10 a.m—on this late-September day. Even in a sport that’s all about pushing the limits, it’s like nothing else.

“Man, you know, it was just this weird idea that we had,” says Andy Chasteen, founder and director of 24HHH. He’s a country boy originally from just over the Missouri border, though you’d never know it. With his flowing locks of dirty blond hair and dharma-bum attitude, you’d expect to meet him waiting on a set of rollers off Maui’s North Shore, not on an Ozark cabin porch or in Oklahoma City, where he runs a climbing gym. He picks away at the skin of a tangerine as we talk. “We were just out here climbing … in early 2006, and the next weekend, I came back here and asked for the owner. Pitched the idea to him, and oddly enough, he didn’t really have any questions. He was just like, ‘Man, that sounds like a great idea.’”

That was nine years ago. With only three or four months to plan that first event, no one was expecting much. Andy and his compatriots figured maybe 30 climbers would show. Instead, 120 competed that first year. But still, with climbers from Arkansas, Missouri and Oklahoma—and maybe a few Texans—as far as these things go, it was pretty much a locals-only affair. But almost immediately, it turned into something more. Something unique.

There’s a lack of pretense, even for the most experienced climbers. It’s something that you can see long before anyone has taken to the cliffs, when you happen to come across world-renowned climber Alex Honnold sitting on a cabin porch eating breakfast. The sun rises over the trees and cliffs behind him hinting at the heat to come. For being the most famous person in the canyon and probably even this half of the state, he’s rather unassuming. There is no ego here. Instead, there’s a messy crop of short brown hair, a friendly face and a bit of an aw-shucks attitude. Surprising, perhaps, for the only person to solo climb (mostly by “free climbing” without aids like ropes and anchor bolts) Yosemite’s triple crown of big walls—Mount Watkins, El Capitan and Half Dome. And it only took him 19 hours. In about an hour, a shotgun will be fired into the air and he’ll take off with his teammate-girlfriend, fighting his way through a crowd of nearly 500 other climbers, and attempt to reclaim the record for top individual score.

But what brought him to Arkansas in the first place?

“I was just told that it was the thing to do.” That is the highest praise.

There are many possible reasons for why this event is so loved in the climbing community. Perhaps, it’s because it’s a grassroots, community-driven operation. (Although, it should be noted, there are corporate sponsors.)

“[Climbers] go to so many events a year that are corporatized, and we are not like that,” Andy says. “We do everything the Arkansas way, really. We’re here in the middle of nowhere, and we’re going to stick with that.”

Or perhaps it’s how the event has taken on a life besides the competition. Talk to anyone, whether they be a competitor, a volunteer or a general hanger-on-er, and sooner than later, they’ll use the word “reunion” to describe the event. This is their yearly chance to see cross-continental friends made in years past. This is their homecoming.

“We have all the new people that show up every year, and they are kind of just thrown into the family. It’s just, ‘Welp, come on in,’” Andy explains. “I think most of the people that have been once are hooked. They come again if at all possible. We have got people now that book a whole week of the year. They take a week’s vacation to come out on Monday and spend all week here.”

No wonder no one is surprised to hear that one of the original climbers has skipped his first wedding anniversary to attend. (Although it is generally agreed that it was poor form to schedule his wedding for this time of year at all. “Idiot! It’s always the end of September!”)

But more than anything, it is the location. Back when it was still known as Lick Hollow, Horseshoe Canyon Ranch’s bounty of sandstone cliffs attracted fence-jumping climbers from all over the region. In 1995, when Berry and Amy Johnson bought the valley to turn it into a dude ranch, they had no idea what they were getting into. But they embraced it. Climbers could stop fence hopping and start camping on the property. More areas were opened up and developed, and today, the valley boasts more than 400 routes with names such as Cotton Candy, Horseshoes and Hand Grenades, and Fatty McFlipflops.

“It’s like an outdoor [climbing] gym out here,” Andy says. “Just route upon route upon route, you know?” Where most climbing spots offer the opportunity to climb maybe five or 10 routes in a day, here a casual day could easily consist of 20. Simply finish one, clear your rope and step over 10 feet to the next.

This year’s winning team will do that 391 times, accruing 77,310 points—points being awarded based on each route’s level of difficulty. That’s nearly one route every four minutes. Alex Honnold will reclaim the individual record with 151 routes and 43,490 points—a rate of one route every 9 ½ minutes. He went for difficulty over speed yet was still pretty darn speedy.

Most climbers will do nothing near those numbers, and that’s OK. Like a marathon, only a small percentage of the competitors go for the win. For everyone else, it is about setting their own goals.

“If they attain that goal that they went for, then they’ve won,” says Andy.