Santiaguito roared throughout the night - a thunderous pop and a rumble followed by low, deep hissing every hour or so.

Our guide, Carlos, rose from his snoring slumber every time, opening the flap of the tent to watch the volcano spit lava, smoke, and ash.

My husband, Jay, and I were lying next to Carlos, just 400 yards away from one of the most active volcanoes in the world. At times, clouds drifted in, making its fits of rage audible but not visible.

The three of us did not leave the campsite during the dark night for fear of being hit by flying rocks or tripping over loose ones on the ground. The few belongings we'd brought - a change of clothes, water, toilet paper - sat in backpacks next to us, where they were protected from the healthy layer of ash coating the world outside the tent.

We'd booked this overnight hike with Monte Verde Tours, an outfitter in Quetzaltenango, as part of a 10-day adventure in Guatemala. Pre-trip research had signaled this would be the kind of off-the-beaten-path experience we sought: Monte Verde offered just one trip every few months. Hardly anything had been written about it. There were no waivers to sign.

We began at a trailhead just outside Quetzaltenango (also known by its indigenous name, Xela), more than 7,000 feet above sea level. It was a two-hour, relatively easy walk to the Mirador viewing point, where we watched the volcano from afar while free-range cows scrounged for grass and greedily approached our snacks. Jay and I, spry at 8 a.m., had strutted along confidently: "We could do this all day!"

Carlos chuckled, but we didn't think anything of it.

It wasn't until we started the steep descent down Santa Maria - one of a series of volcanoes in the Sierra Madre mountain range across a deep valley from Santiaguito - that we began to fully appreciate the difficulty of the trek. It was less than nine miles to our camping spot, and we'd be going 3,000 feet down Santa Maria and then 1,500 feet up Santiaguito in conditions requiring climbing, sliding, and shimmying.

Like Santiaguito, Santa Maria is still active, though rarely. Its 1902 eruption was one of the century's most explosive, after being dormant at least 500 years. We tried not to think about that as we teetered beneath our packs. (Two days' worth of water is pretty heavy.)

Carlos wielded his machete like a ninja, cutting through the thick shrubbery that engulfed our path and enveloped our feet. There are no switchbacks or trails to make it easier for tourists. His long, black hair swayed, kept out of his face by a rolled bandanna.

When it came time to carefully navigate slippery volcanic rock chutes, Carlos helped by putting my pack on his head (in addition to carrying his own on his back). With his small frame, he leaped ahead of us with ease as Jay and I crab-crawled down on our behinds. Out of curiosity, I asked Carlos whether he had a first-aid kit or cell service. "Not really," he said.

Reaching the bottom of Santa Maria seemed like a feat. Feeling victorious, we took big swigs of water, a snack break, and smiley photos. Fog sat low in the valley, a moonlike bed of sharp, craggy rocks. I stepped carefully around them, my pack swaying with every step. We wore bandannas over our mouths so we didn't inhale the fine dust blowing in the warm wind.

Carlos told us about himself: He and his partner had a daughter. Before learning English and becoming a guide, he'd worked in a tire factory, which he said paid very little by comparison and offered no advancement. I got the impression he enjoyed making this trek even more than we did. Carlos admired our hiking shoes and the W.L. Weller bourbon we'd brought from home in a flask. (Hey, we deserved a liquid reward at the end of this day.)

We were still only little more than halfway to our campsite, and it was all uphill from here.

Two hours later, we were so tired we felt like quitting, but we couldn't. The only way out was to hike back down and up again or get a helicopter, and neither was an option. Santiaguito has several plateaus on the way up, each resembling a new climate. The first plateau was dewy with tropical greenery and plants; another was dusty and desolate. Camping would be possible on any one of them. Nauseated from altitude and fatigue, Jay wanted to stop at the first, but we coached each other and pressed on, knowing what we'd come for was within reach. Finally, we made it to our goal, the plateau campsite closest to the hissing, smoking crater.

Pasta cooked on a hot plate with ketchup for sauce never tasted so good as it did when the three of us ate huddled in our tent that evening. Sunrise came early after a restless night, but we felt surprisingly refreshed. By now, Carlos seemed like an old friend; I suppose sleeping next to a stranger a short distance from an active volcano could make anyone feel closer. He said we should treat this vantage point with respect and asked us to make a wish. Then he lit a candle, climbed with it to the top of a large rock, and knelt to pray while Jay and I collected our thoughts and prepared our minds for the trek back down.

We'd been able to hoist ourselves up large, stable rocks on the way to Santiaguito, but coming down required balancing our weight while sometimes carefully placing our feet at a 90-degree angle into footholds not easily seen. Carlos descended each part first, grabbing our packs so we could climb down more safely.

We knew from the previous day's experience the second, uphill leg of our return hike would be much more exhausting. By the time we'd gotten back up Santa Maria's volcanic chutes and into the jungle paths, each leg felt as though it were attached to a cinder block. I began chanting to myself: "Strength, motivation, clarity. Strength, motivation, clarity." Jay encouraged and pushed me. We had to take more rests than on the first part of the trip, and it became clear we wouldn't make our scheduled group shuttle to San Marcos La Laguna on Lake Atitlan, our next stop.

Meanwhile, Carlos was hopping ahead like a mountain goat. He told us he once led a Dutch family on this journey for a moonlight viewing of Santiaguito. They made the trip in half the time we did, even in the dark, and didn't have to stay overnight.

"The most important thing is to stay happy on the mountain," Carlos said. We knew why: If you're not happy, you'll barely make it. We began to change our attitude, congratulating ourselves each time we made it to a landmark we recognized. We practically screamed with joy when we saw those snack-mooching cows, even though we still had an almost two-hour (flat) walk until the end.

Monte Verde's owner, Josh, met us at the trailhead with several liters of water, which we had run out of hours earlier. He also bought us beers at a market nearby and arranged for Carlos to drive us to Lake Atitlan. Carlos stopped in town, where his daughter and her mother hopped in the front seat of the van with him. They laughed and talked as we stopped for soda and ice cream at a roadside stand along the way.

I lay in my seat all the way back, utterly exhausted, and grabbed Jay's hand. We laughed, too. We couldn't believe what we'd just done. But we knew that when you take one step at a time, you eventually come out on top.