I was bushwhacking through a tangle of shrub and trees, following the Gila River in southwestern New Mexico, when I came across fresh bear prints in the wet, sandy shores.

Big bear prints.

I shouldn't have been surprised. After all, the wrangler who led me on several horseback trips through the Gila Wilderness the previous three days packed a shotgun on his saddle.

Alone, unarmed and pushing through a snarl of brush, I was searching for a hot spring along the riverbank. Aldo Leopold, the legendary ecologist and forester who campaigned for the protection of this untamed land, soaked in this and other nearby hot springs more than 85 years ago. But I couldn't find it amid the trees and bushes.

As the shadows lengthened and the woods came to life with sound, I saw nothing but limb-biting branches and more animal tracks.

Like thousands of travelers who visit the wilderness annually, I had come to see the hardscrabble patch of New Mexico that became the model for every protected wilderness in the country. I came to explore the same rocky trails cut by the Apache warrior Geronimo, homesteaders and gun-packing fugitives. But most of all, I wanted to see whether America's first wilderness area -- protected 84 years ago from roads, cars and other modern intrusions -- was still as pristine and untamed as Leopold had intended.

Surrounded by towering canyon walls and clawing tree branches, I could see that Leopold's vision for this land prevailed; it was beautiful, wild -- and even a bit scary.

East of the Big Nothing

From a nighttime satellite photo, these half a million acres of arid mesas and canyons look like a huge, black hole bordered by the scattered blinking lights of Silver City to the south and Truth or Consequences to the east, and a big nothing to the north and west.

Cars, roads, railroad lines and cellphone towers are prohibited in the wilderness. To reach this heart of the darkness, you strap on a pair of hiking boots or mount a horse.

Leopold preferred the latter. As a forester in the early 1900s, he defined a wilderness as a protected area "big enough to absorb a two weeks' pack trip."

The Gila is certainly that big, but I didn't have the patience for a two-week trip, so I planned a four-day outing in late May, joining a group of about 30 horse enthusiasts from South Carolina who were visiting some of the best riding trails throughout the nation. They had no set agenda except to explore the wilderness on horseback for several days while camping in the national forest on the outskirts of the wilderness. They welcomed me into their camp, and by the end of the visit, they had me -- a native Californian -- speaking with a twang.

To get to our campsite, just outside the wilderness area, I drove three hours southwest from Albuquerque followed by an hourlong, teeth-jarring trek along a washboard dirt road through the Gila National Forest. Along the way, elk the size of ponies bounded across the road and into stands of ponderosa and juniper trees.

As I pulled into the campsite -- a collection of tents, horse trailers and pickup trucks -- I was greeted by Ben Marlin, a wrangler and former rodeo champ whom I had hired as my guide through an outfitter called Gila Wilderness Ventures.

Despite losing a thumb in a cattle-roping accident years ago, Marlin gave me a vise-grip handshake, and I knew instantly he was the right man to show me the wilderness.

Marlin, wiry and energetic, rode and roped bulls in Nebraska before he dropped by this corner of New Mexico 15 years ago. He came to visit a buddy and never left. This land -- rugged and genuine, just like Marlin -- fits him, he says, like a pair of worn jeans.

That night, I wrapped myself in a down sleeping bag on a cot in a roomy tent. He slept on a tarp on a patch of dirt next to his horse.

The next morning, Marlin was eager to ride into the wilderness to show me a cave thought to have been used by Native Americans as a granary. We didn't wait for the South Carolinians to finish a leisurely breakfast. Instead, we ate quickly and rode across a long mesa studded with juniper trees and short, golden grass.

At the end of the mesa, we zigzagged down narrow switchbacks to the banks of the Middle Fork of the Gila River.

After two hours riding a dusty single-track trail, we found the granary burrowed into the side of a rocky hill. The opening of the 2-foot-tall cave was shaped by aging masonry. Marlin was unsure whether the Mogollon or the Apache had stored corn in the cavity. It might also have been a hideout for Geronimo or for fugitive outlaws. After all, Butch Cassidy and the Wild Bunch were also known to roam these parts.

"There's a world of history in this wilderness," Marlin said as I poked my head into the cave.

The history of the Gila Wilderness starts with the chapters on the Mogollon people and the Wild Bunch. But perhaps the most significant character in this story was Leopold, who joined the U.S. Forest Service in 1909 and took his first assignment in the Arizona and New Mexico territories.

In the early 1900s, roads and mass-produced cars began to splinter the American landscape. Inspired by Henry David Thoreau and other preservationists, Leopold campaigned to protect America's remaining tracts of wilderness from destructive cars and the attendant blacktop.

"Wilderness is the raw material out of which man has hammered the artifacts called civilization," Leopold wrote later in his book, "A Sand County Almanac."

The headwaters of the Gila River, he decided, were ideal for his proposed "road-less" wilderness status. It's easier to preserve a pristine wilderness, he argued, than to try to rehabilitate tilled and paved land.

Leopold persuaded the regional office of the U.S. Forest Service to designate the land a wilderness area in 1924. Forty years later, President Lyndon Johnson signed the Wilderness Act, creating a national standard for protected wilderness areas.

Gila was the prototype for the more than 700 wilderness areas now designated throughout the country.

The stars shone that night like distant headlights in a coffee-black sky. I relaxed around a campfire with my fellow equestrians as we sipped hot chocolate, wine and beer and tried to decide whether that tiny red dot just above the horizon was really Mars.

After we turned in for the night, a pack of wolves circled our camp, spooking a few horses and waking some campers. The culprits, Mexican gray wolves, were released into the Gila in an effort by the U.S. Fish and Wildlife Service to reintroduce the nearly extinct animal to its natural habitat. The program began in 1998 with seven wolves. Now they number more than 50.

Some nearby ranchers have criticized the wolf program, including those who have lost livestock to the packs. The debate between ranchers and supporters of the wolf program cuts to the core of how best to manage -- or not manage -- a wilderness area. If the idea of a wilderness is to leave it unaltered and pristine, should wildlife that was hunted and trapped nearly to extinction decades ago be reintroduced? And if so, why is the forest service still issuing permits to let ranchers' cattle graze within and adjacent to the wilderness?

On the morning after the wolf encounter, a small group of us rode into the wilderness. We noticed Marlin had strapped a shotgun to his saddle.

"What do you plan to shoot with that?" a rider asked.

"Whatever needs killin'," he answered calmly.

I began to wonder whether this was a sign that the wilderness remained as pristine and untamed as Leopold had envisioned so many years ago.

We followed Marlin along the Middle Fork of the Gila River in the shade of ponderosa pine, juniper and fir trees to a flat, grassy meadow near Flying V Canyon. Rust-colored, craggy rock pillars line the canyon walls.

In the meadow, we rode up to a collapsed log cabin, blackened by time. Marlin said the cabin represented the remnants of an old homestead shack, one of only 10 or so in the wilderness.

Many people tried to settle the Gila, Marlin said, but the land was just too rough to tame.

In search of a hot spring

The next morning after breakfast, I said goodbye to Marlin and my South Carolinian pals and began the long drive to the end of the wilderness, near the Gila Cliff Dwellings National Monument.

A ranger at the monument gave me a map to a secluded hot spring, only a mile and a half hike from a roadside parking lot along the Gila River.

By midafternoon, I had hiked at least two hours through cottonwood branches and shrub but couldn't find the spring. My water bottle was nearly empty. Frustrated and hot, I cursed myself for venturing this far alone.

As the sun began to sink behind a pine-studded mountain, I gave up on the hot spring and turned back. Thick brush cut my legs. I spotted elk, bear and wolf tracks in the sand. Finally, I saw a tall concrete bridge, near where I had parked my car. Now that I saw my escape from the wilderness, I relaxed and pulled off my shirt, hat and hiking boots and sank into the river, letting the cool waters wash over me.

In my head, I heard Marlin's country twang, saying, "This is about the wildest place in the country, and I don't think it's ever going to change."

He meant it as praise for the wilderness, but I should have taken it as a warning too. That's the beauty of this beast.