Rock climbing in this secret gem is as captivating as it is tough, and the more you know about its history, the stranger it gets.

On the western outskirts of Colorado’s San Luis Valley, narrow canyons form hallways of hard volcanic rock, rounded smooth from wind and rain. Corridors are hidden among grassy plains, where secret societies once roamed, worshiped and practiced their faith with rituals of startling and harsh dedication.

Los Hermanos de Penitents, the Brothers of Pentinence, of the 19th and early 20th century were persecuted for reenacting the suffering and death of Jesus Christ. Their practice included whipping, flogging and even carrying of a heavy wooden cross for Lent, a significant week of worship for certain sects of Christianity.

Today, the Penitente Brotherhood is free to practice in public. In fact, in Taos, New Mexico, it’s celebrated.

And today, a different kind of disciple frequents Penitente Canyon where they once practiced. One dedicated to fighting natural forces: Gravity, inertia, strength.

They’re rock climbers. A band of athletes so misunderstood it takes those unfamiliar with the culture a few days to even begin to comprehend their essence.

They spend their hours in excruciating situations. Negotiating sheer, blank walls and edging their way up faces, vertical and beyond.

Their fingers bleed. Their toes swell. The level of fitness that develops from days, months and years of this obsession is incomprehensible. Muscles inflame, endurance and toleration skyrockets. All to climb an unlikely path to the top.

It’s a beautiful thing.

“It’s really beautiful climbing,” said Jared Slota, a Colorado climber of 10 years who seems to have a devout skill for the nature of the routes at Penitente. “The rock is beautiful. It’s unique climbing, Core intensive. Balancy.”

The act of rock climbing, which is up there with swimming for calories burned per hour, is as physical as you can get. Your entire body becomes engaged in the relentless pursuit of pulling and pushing. A balancing act in the middle of powerful gusts of strength. A call on one’s every athletic ability, all while remaining calm 30 feet off the ground.

Often, that’s the hardest part, and for these niche athletes, the best. In Penitente, the notion of suffering and overcoming fear for enlightenment comes with the territory.

“Fear,” said Corey Wright. “It’s nerve-wracking. It’s awesome to be that scared and out of your element, and once you make that move, in my eyes, there’s not a better feeling. “