Rising to face unexpected challenges and adversity, a young explorer scout takes a pivotal step toward the man he is today.

They said nothing, our leaders, about where we were headed. I was 14; we were a group of 20 or so explorer scouts hiking through the cool, piney umbrage of the Adirondack Mountains. Long hikes had become a daily routine that summer, and this one seemed to be following the usual protocol: a 4-5 mile trek out from our base camp, culminating with a swim in a lake clear-black with the essence of peat, wood mushroom and crisp night sky.

I was somewhere in the middle of our single-file procession, a lower-ranked scout seeking more merit badges. A handful of troop leaders and senior scouts led the way; a few more pulled up the rear. Little Ralph DaSilva, my camp bunkmate, walked directly in front of me. A textbook braggart and foul-mouthed bully, Ralph compensated for his lack of size with swagger; in camp, he had the lot of us smoking sawed-off twigs of grapevine, cursing like sailors and backing down from his ongoing threats. Ralph was our de facto leader; his voice, as usual, echoed the loudest that morning among the forest’s stout pines.

Then a hand shot up at the front of the brigade, and we came to a stop. At the base of a huge white pine was a narrow opening; it looked like something a fox might have dug. We watched in silence as, one by one, our fellow scouts descended into it and their heads disappeared into the earth.

Briefly I entertained the thought of turning and running, but I’d never do so in Ralph’s presence. Drafting off his apparent cool, I followed him and the others into the hole: down to a brief, earthen landing, then a steep, 15-foot descent along a narrow stone ledge, leaving behind the last rays of daylight for the earth’s dark chill.

Within a few moments, we were all gathered in a massive underground cavern. Our voices clamored, and flashlight beams coursed over craggy rock walls that everywhere dripped water into an icy stream beneath our feet. We were told to reassemble into a single file, and soon we’d resumed our morning’s hike, only underground now and back in the very direction from which we’d just come, as though retracing our steps in a mirror.

The first big cavern soon gave way to another, and another. The walls narrowed ever so slightly as we proceeded, and the stream slowly rose up around our boots and our calves, and then our knees. We seemed to be walking even longer and further than we had above ground; our collective awe distended time and distance, propelling us past any original hesitations or fear. It was as if we were living out some boyhood adventure fantasy. Ralph carried on the whole time about the other bigger, better, and scarier caves he’d already explored. I – a Brooklyn boy with only the subway as a reference – was bracing myself for an imminent encounter with hobbits.

The water we walked in continued to rise, however, and with its icy chill our once-animated voices grew increasingly breathless and pinched. There was as much looking back over our shoulders as there was curiosity about what might lay ahead. Yet no self-respecting teenage boy would dare retreat, for the lasting humiliation it would bring. So on we all marched, our voices, even Ralph’s, steadily dwindling into nervous whispers and then complete silence as a hand rose up again at the front of the line.

A solid cave wall lay ahead. I watched once more as the heads of my fellow scouts disappeared, this time making a sharp left. I figured, eagerly, that we had finally reached the pivot point – the entrance into the first of an ever-widening series of caverns that would lead us back out, just as the previous ones had led us in. Instead, we turned and filed 100 yards down a corridor of opposing rock faces, the walls closing to barely shoulder-width and the water rising up to our chests. In another 50 feet, we confronted our fate. Water and wall melded into a full stop; the only exit was an underwater passageway eerily limned by the submerged tendrils of outside daylight wavering in all around us.

If there were any remaining doubts about what was expected of us next, they were immediately dispelled when two of our advance troop leaders promptly took deep breaths and disappeared through the passageway. A moment later, we could hear their suddenly remote voices calling back to us from the far side, at which point the fuss began: an otherworldly, prayer-like chorus of frantic murmuring and whimpering that was soon overwhelmed by the full-fledged screams and cries of Ralph DaSilva.

I completely empathized with him. Yet something about the unlikely prospect of my rough-tough bunkmate going all to pieces there in front of me worked to mitigate my own terror. Amidst the rising clamor and the repeated appeals for calm from our rearguard troop leaders, I unexpectedly found myself leaning in Ralph’s direction, riding his panic by way of calming both him and myself. I’d never thought of myself as a brave or levelheaded kid. But when one of the leaders asked, in clearly demeaning tones, if someone could help “poor Mr. Da Silva,” there I was, volunteering my services. Ralph DaSilva, of all people, someone I’d never had the courage to stand up to in the face of all his hectoring, had scared me into feeling responsible for him.

I put an arm around Ralph’s quaking shoulders, rubbed his back, and escorted him to the rear of the line. This would allow both of us some time to watch the others, one by one, take their deep breaths and make the furious swim to freedom. When our turn finally came, I told Ralph he should go first, that I’d be right there behind him. But he insisted that I lead; he’d rather follow me. I remember looking back at one of the troop leaders and exchanging a quick nod. I then wished Ralph luck, took my breath, and swam like mad.

It was no farther than 6 or 7 feet, it turned out, before we were met by the waiting grasps of our troop leaders, pulling each of us back up into daylight and euphoria. Moments later, Ralph DaSilva was back among us as well, wildly exultant, triumphant, and, true to form, quick to tell us how insignificant the ordeal had been compared with his other cave exploits. Still, his voice had a whole other tenor now. Things had changed, and he knew it. We were on the far side of our previous selves, and all at once I felt so much older than my years, as though I’d just met for the first time the man I might become.

Charles Siebert is a contributing writer for The New York Times Magazine and is the author most recently of The Wauchula Woods Accord: Toward a New Understanding of Animals.