Katmandu is not Hemingway's Paris or Paul Bowles's Tangier. Yet the dusty, impoverished capital of Nepal is an expatriate Eden in its own right. Full of art thieves, smugglers, renegade anthropologists, restless foreign service spouses and an array of Western dharma bums, it has been a haven for a colorful collection of characters who make up what has been called "the Rock-and-Roll Raj." With names like Eight-Fingered Eddy, Dutch Bob and Saddhu George, these are people who've devised "ways of escape" from the West in a fashion that Graham Greene would have appreciated. Driven by the pursuit of exotic experience and arcane knowledge in their most intense form, it is a community where the sacred mixes freely with the profane, devotion and decadence are often hard to tell apart, and the taxman doesn't cometh.

Like many expatriate communities, Katmandu's is known for throwing good parties--and a lot of them. One of the most memorable celebrations was held in 1984 in a refurbished 15th-century temple to mark what its host, a German architect, said was a rare, once-in-the-century "opening" of the stone lotus flower that was carved into the temple's courtyard. The German architect had sent out invitations to most of Katmandu's expatriate residents, inviting them to witness this once-in-a-lifetime occurrence. They responded with enthusiasm, and the "Opening of the Stone Lotus Party" left an impression that still has those in attendance talking about it.

In the Eastern meditative traditions, the lotus is a symbol of human consciousness, and its "opening" is regarded as a metaphor for enlightenment. But at this party, the "opening of the stone lotus" was clearly a put-on, the German architect's ironic commentary on the expatriate community's easily parodied yearning for esoteric knowledge and spiritual communion. Most of those in attendance that night knew from the get-go that it was all a joke on them; those who did not seemed to have figured it out along the way, high on the glow of butter lamps, the tinkling strains of Philip Glass, and the dreamy hashish smoke for which Katmandu is internationally renowned.

Ian Baker, a 41-year-old American resident of Katmandu for most of the last 20 years, was in on the party joke from the beginning. But for this member of the city's small caste of self-styled scholar-adventurers, the stone lotus did eventually open up, at least in a certain way.

In January the National Geographic Society announced that Baker had led an expedition into a remote mountainous area of southeastern Tibet called Pemako-- "The Hidden Land of the Opening Lotus," as it is known in Tibetan. There he had discovered a long-rumored but never before documented major waterfall on Tibet's mighty Tsangpo River. Clawing their way down mist-cloaked, nearly sheer 4,000-foot cliffs into a rocky gorge-within-a-gorge so deep it remains in perpetual shadow and can't even be seen on satellite surveillance photographs, Baker and another team member were able to reach and measure a waterfall approximately 108 feet high, naming it Hidden Falls.

Although its ferocious currents and heavy rapids make the Tsangpo known as the "Mount Everest of rivers," the waterfall itself is not overwhelming in size, at least by international standards. (Niagara Falls measures 182 feet.) Its discovery, however, does represent significant unfinished business from the classic age of Victorian-era exploration. At one point the search for the headwaters of the Tsangpo--which becomes the Brahmaputra as it crosses the border into India--was considered just as significant as the search for the source of the Nile. And long after Victoria Falls, the Nile's source, had been discovered, the great falls of the Brahmaputra remained an obsession, a fabled but unseen wonder.

Baker's discovery was also accompanied by lots of talk about the area being a kind of earthly paradise, a la "Lost Horizon"--a lush subtropical garden of stunning biodiversity resting in the world's deepest gorge between two Himalayan peaks each around 24,000 feet high. "If there is a Shangri-La, this is it," said Rebecca Martin, director of National Geographic's Expeditions Board.

Cliches aside, the area around the Hidden Falls really is Shangri-La--or at least one of the landscapes that gave birth to the centuries-old Tibetan myth of a hidden paradise that came out to the West as Shangri-La. Indeed, according to myth, Pemako is a "hidden land," or beyul, and the waterfall at its center conceals a doorway to a paradisiacal realm, through which pilgrims of requisite spiritual refinement might pass.

The romance of legend, and the falls's elusiveness, combined to make it perhaps the last great "discovery" of Western explorer-adventurers. And though Baker clearly passed through no door to spiritual paradise by finding the falls, he arguably entered an earthly one, consisting of half-million-dollar book deals, instant celebrity and movie rights to come.

But Baker claims to merely be surviving all that. His real interest, he says, is meeting "one of the challenges of the 21st century . . . to redefine what 'exploring' something really means."

Besides, he said, there really was some kind of opening near the falls, an opening that was inaccessible, but visible. He still can't help wondering what's on the other side.

The Lure of the East

The first time Ian Baker heard the word beyul, it was in a Katmandu antique store in 1984, shortly after the 26-year-old had become an expatriate. Combing through tanka paintings, ritual masks and centuries-old sculpture, Baker overheard the proprietors discussing the exploits of a certain Tibetan lama who had recently returned from a journey to a "hidden land" tucked into a remote area on the Nepal-Tibet border where his meditation-induced visions were marked by an unusual intensity attributed to the power of the place itself.

The story of the Hidden Land rang a big bell with Baker, a recent Middlebury College graduate who had majored in art and had a keen interest in the anthropology of remote Himalayan cultures. During his junior year, Baker did a semester-abroad program in Nepal. The experience left him with a passion for the East that would define the course of the rest of his life.

Graduating in 1980, Baker was given a fellowship from the Explorers Club in New York, which would take him into the tiny kingdom of Sikkim to study shamanic traditions. But first, he had a serious climbing accident in Norway--he fell 70 feet and fractured his skull. His full recovery--at first seriously in doubt--took more than a year, but by 1983 he had taken up full-time residence back in Katmandu, becoming an academic director for the college program he had been on as a undergraduate. In his time off, he continued research on shamanic traditions, taking him into regions of Nepal that had only recently been opened to foreigners. Inspired by the lama's story, Baker tracked him down in the mountains and expressed interest in going to the hidden land, where the lama had been.

"It's not just a place to go take pictures," Baker recalls the lama explaining. But once Baker conveyed his serious interest in the spirituality of the search, the lama told him to come back in the summer, and be prepared to spend a month alone in a cave. When Baker returned, the lama sent him off with two nomads who led him to a cave deep in a remote valley.

There Baker sat alone, meditating for a month. Baker says that in the Tibetan Buddhist tradition, "it is considered bad form to recount one's inner meditative experiences." But he will say that there were "vivid dream states in which my mind felt strangely porous, alert to images and impressions normally veiled from consciousness." At one point, he says, he perceived "two circling fireballs" that seemed to be floating through the valley.

Although he was entranced by the legend of the Hidden Lands, Baker's interests throughout the 1980s were far-flung. In addition to his academic duties, he led trekking tours, collected and dealt in art and antiquities, and learned how to speak and read Tibetan.

During most of the 1980s, Katmandu was a wild, freewheeling place with an active underworld that was practically given official sanction by Nepal's corrupt royal family. Within the expatriate community, art piracy, gold smuggling, hashish trafficking and other nefarious activities were common sources of income enhancement. Those years also saw a revival of interest in the country's tantric traditions, particularly its celebration of "erotic mysticism," as Baker phrases it. Curious Westerners took instruction from a variety of tantric yogis and fakirs, whose lithe, young yogina assistants taught things the readers of family newspapers shouldn't know.

Baker remembers this period as a time "when the normal rules and standards of behavior didn't seem to apply." He admits that an outsider might see a contradiction here and question how someone who professes devotion to Buddhist precepts, as he does, could rub shoulders so feely with those involved in such worldly corruption. But in tantric belief, he points out, true spiritual liberation requires an equal awareness of vice and virtue, and that the sacred and the profane aren't necessarily in opposition.

In the 1990s, though Baker was still occasionally attracted by Katmandu's tantric lures and snares, his life entered into a more industrious stage. He founded Red Panda Expeditions, an adventure travel company, co-authored a popular ethnography about daily life in Tibet, and wrote the text for a book about the Tibetan art of medical healing. (This second book was a big hit with the celebrity-Buddhist set; at the book party in New York, Naomi Campbell and Madonna were in attendance.)

But he hadn't abandoned his interest in the beyul tradition. The lama who'd sent him off to the cave told him beyuls were described in obscure, coded texts that dated from the 8th century. Eager to get his hands on some of them, Baker sought help from the Dalai Lama himself. In Dharmsala on academic business in 1987, he expressed his interest during an audience. Getting a "faraway" look in his eye, as Baker recalls it, the Dalai Lama directed a monk to help Baker locate a dusty tome from a high, dimly lit shelf in the Dharmsala library. This, like other similar texts, was, as Baker puts it, a kind of "Fodor's Guide to the fourth dimension," which advised pilgrims on how best to navigate landscapes that are invested with spiritual and mystical properties. Baker eventually expanded his collection of beyul texts to nine.

By this time, he had begun to focus his energies on Pemako, one of the most revered of all Tibet's hidden lands--"a celestial realm," the mystic Padmasambhava had called it. "Even to take a single step toward Pemako," the sage had written in one of the sacred texts, "is to be liberated from mundane existence."

Another 17th-century text explains: "Whoever practices meditation in this place can accomplish in one night what in other places can be attained only after one year." Some of the lamas Baker has interviewed claim that the area's intense spiritual charge can actually help them meditate a hole in time and space, allowing mental if not physical access to a realm beyond ordinary sensory experience.

In a 1997 article in the Explorers Journal, Baker described the 30-year-old written account of one visionary lama who said his meditation brought him through a waterfall into a tunnel, at the end of which was a pagoda-roofed temple on a small island rising out of a luminous stream. When he reemerged from the waterfall to tell his companions, the way mysteriously closed behind him.

But even for nonbelieving Westerners, Pemako held a unique appeal, both because of its geographic features and what it represented in the tradition of exploration. Cut by the 1,800-mile Tsangpo River, Pemako's gorge is three times as deep as the Grand Canyon. In the 19th century, British geographers had been convinced that only the existence of a colossal waterfall could explain how the river could fall 11,000 feet in the space of 200 miles as it emerges from the Himalayan region at the Indian border.

Hostile local tribesmen and some of the world's most treacherous terrain made it difficult for Western explorers to map the area, however, and up to the time of Baker's last expedition, a full five miles of the gorge had never been tracked.

In 1924 the famed British botanist Frank Kingdon-Ward led an expedition into the Tsangpo's innermost gorge, and described "a howling river . . . boring ever more deeply into the bowels of the earth." Despite arduous efforts, Kingdon-Ward kept running into dead ends of sheer cliffs, and was forced to abandon the effort. Finally returning to London, Kingdon-Ward declared that no falls existed, and that talk of a major waterfall was nothing more than religious myth.

After Kingdon-Ward, the Chinese prohibited foreign expeditions into the gorge until 1992. Then, in 1993, Baker was asked by Rick Fisher, an international outdoorsman and self-described "canyoneer," to become a translator for a white-water rafting expedition down the river, which had the blessing of Chinese officials. Also on the trip was Ken Storm Jr., a Minneapolis businessman and part-time explorer who was obsessed with Kingdon-Ward and the legend of the falls. Declaring that it would have been suicidal to attempt the Tsangpo's stupendous swells and currents, the group abandoned the rafting bid. But Baker and Storm, leaving Fisher behind, decided to follow Kingdon-Ward's old route, using the explorer's sketchy, ultimately unreliable maps that they had photocopied out of old books.

Partway along the trail, they ran into celebrated mountaineer-filmmaker David Breashears and Gordon Wiltsie, another noted climber and photographer, who were also trying to get into the parts of the gorge that had yet to be traced. Breashears and Wiltsie had gotten far enough to see what, from a considerable distance, looked like it could have been a waterfall of significant size. But the gorge's towering cliffs proved insurmountable, and they were able to get no closer than this perch. Facing balky porters who refused to take any more risks, the two were forced to turn around and reduced to eating a large monkey that had been killed by a leopard.

Moving ahead on their own, Baker and Storm themselves got horribly lost, then ran out of food and had to survive by using their climbing ropes to snare wild takin, small oxlike creatures that can climb like mountain goats. After several desperate days, they chanced upon two native hunters who led them out.

The Hidden Land

Over the next five years, Baker made seven more trips into the gorge. While the sacred texts were hardly topographical guides, their many references to routes and landmarks, including a great falls, "seemed to be too specific to be mere guesswork." Journeying into and out of Pemako involved a nearly three-week trek across hair-raising terrain, from monstrously steep, scree-covered slopes that offered few footholds to mossy, mist-covered ravines filled with pit vipers and jumbo leeches. Along the way there were also mysterious trees and plants with stinging nettles that gave anyone who touched them hives, boils and rashes. The terrain on the last leg of the journey was so rough that it took five days to cover the last 10 miles, much of it along bamboo-choked 45-degree slopes that dropped off into solid rock cliffs free-falling to a churning river.

Equally tough were the subsistence hunters living on the edge of the gorge itself, descendants of the naked headhunters who had greeted the first Buddhist pilgrims in the 17th century. According to the porters who assisted Baker, these Monpa tribespeople follow a "poisoner's cult," believing that if they can poison a traveler, they will absorb the victim's good luck. The idea spooked the porters enough that they refused food and drink offered by locals along the way.

On Baker's first trips into the area, the Monpa told him that they'd never heard of any great waterfall and that there were no routes into the part of the gorge Baker wanted to explore. But on an expedition late in 1997, part of the group reached a spot several thousand feet above the river where they could see some kind of sizable "hydraulic event" down in the chasm--something very similar to what Breashears had spotted and photographed in 1993. Until they got closer, they could not be sure that what they were seeing was not simply a steeply graded set of rapids throwing off a lot of mist.

The following May, Baker returned. He and an associate named Hamid Sadar, a Harvard PhD candidate, went out one day to photograph some takin in the wild. They chanced upon some trails heading down into an area of the gorge that the locals had always said was inaccessible. One guide, an ethnic Tibetan named Tsering, first seemed disturbed. Then he looked at the sky, which was uncustomarily cloudless in a place where fierce downpours often occur for weeks on end. The clear skies were taken as a good omen, Baker says, an indication that the guardian deities were giving the go-ahead to reveal the secret.

Tsering, says Baker, "told us that until now he and the Monpa had never told any outsiders that there was a way down into the innermost gorge. But we had returned year after year, spoke their language, knew their ritual practices, and they accepted us now as nangpa, or Buddhist insiders."

The other hunters agreed that it was time to trust Baker. They had never actually dared to go to the falls, out of fear of the protector spirits, but they had seen it from a distance. Now they demanded that Baker take them to the hidden land.

"They expected us to take the lead," Baker said. " 'You've had all the initiations,' they said, 'met with all the great lamas who had to flee from Tibet. You have the karma to open the hidden land!' "

Following Tsering's directions, Baker and Sadar clawed their way down into the gorge. Following takin trails down precipitous landslides and through dense jungles, they came to the edge of a cliff hanging over a waterfall "of significant proportions," which was throwing up an enormous column of mist and was almost assuredly the fabled falls.

They also saw why Kingdon-Ward had given up only a quarter-mile from that spot in 1924. Unless you were right in front of them, the falls were completely obscured by a hairpin turn in the river as well as a rock spur created by the intersection of two mountains. But lacking the time and supplies, as well as the proper measuring equipment to make the demanding descent worthwhile, Baker and Sadar decided to wait for the following autumn.

In late October of last year, with a $40,000 grant from National Geographic, Baker led another expedition into the gorge. At the end of the first week of November, the expedition followed the steep takin trails into the gorge's innermost sanctum to the edge of the cliff where they had seen the waterfall the year before. Then Baker, Ken Storm and a National Geographic videographer roped down to the thundering cataract and made the needed measurements. The fact that the most frequent reading they got on their measurement device was 108 feet was an interesting coincidence, he says, given the significance of that number in the Budhist faith, its 108 "auspicious signs" and the 108 beads carried on a Buddhist rosary.

At the bottom of the falls, Baker stood in what he describes as a "sunless grotto." Beside him the Tsangpo, whose entire volume was being funneled into a flume barely 60 feet wide, was a seething maelstrom that made it impossible to hear almost anything else. Looking at the snows of the peaks towering almost 20,000 feet overhead, he says, "felt like being at the bottom of the Earth."

But what has stayed with him even more than the physical sensation of that moment was the spiritual aura. He was a Western explorer solving a geographic riddle, but he was also a pilgrim who had traveled into the heart of the lotus in sympathy with local tradition.

"At that moment I felt like I was standing at the flap between two worlds, as if a door between the two worlds had been flung wide open and a wind from the other side was hitting me in the face."

Just then, he heard a voice over the roar. It was Buluk, one of the hunters, who had scrambled down to the falls with Baker and Storm. "There's the door!" Baker recalls Buluk saying. To which Baker responded, "What door?"

Buluk answered: "The door to Yangsangne--the secret-most sacred place."

Baker looked through the expedition's range-finder binoculars and saw an oval opening on the far side of the falls that was cut into the cliff face about 20 or 30 feet above the river's raging currents. It was not an optical illusion formed by shadows, Baker insists, nor was it a shallow cave gouged into the mass of rock that spread around it. Rather it was a passageway that gave way to "a clear tunnel veering off diagonally into the dark heart of the mountain," although just how far into it was impossible to tell.

The skeptic in him was, of course, dubious about the cut being a literal doorway to paradise and shrugged it off as a geological oddity, at most the real-world referent for the "doorway to paradise" mythology. But the spiritual seeker in him thought it wouldn't hurt to entertain some good old magical thinking.

"For the Tibetans it really was the doorway to the lost world," he explains. "And that they believed so is perhaps all that really matters."

Ever the explorer, Baker did press the hunters on whether they knew a way to get to the door to investigate.

"That's just the problem," they told him. "There's no way over there."

Trouble in Paradise

Baker returned to the States in January to make a formal presentation of his findings to National Geographic and to be photographed for a spread in the May debut issue of the new National Geographic Adventure magazine, which lauded him as an "Explorer for the Millennium."

Media attention--CNN, the Wall Street Journal and other national and international news organizations--triggered heated competition in the publishing world for the book about the quest that Baker plans to write. Random House, seeing an adventure travel classic in the manner of Peter Matthiessen's "The Snow Leopard," offered a $500,000 advance without even requiring Baker to write a proposal.

But Baker's victory lap--and newfound wealth--was not completely fret-free. Like Richard Burton when he announced his discovery of Africa's Lake Victoria in 1859, Baker was almost immediately challenged by rivals. The most vociferous attack came from Rick Fisher, the river guide who had first introduced him to the Tsangpo Gorge in 1993. Fisher maintained that Baker was hardly the first to reach the falls, contending that Chinese teams had been there years before. He also claimed that National Geographic was participating in a hoax, and had used computer technology to doctor photos showing Baker at Hidden Falls. Fisher got even more outrageous, accusing Baker of engineering the systematic slaughter of the "endangered" takin and of actually beating one baby takin to death with a rock and stuffing its raw flesh "into his blood-spattered face" in front of eyewitnesses.

The National Geographic Society, Fisher advised, should reject Baker's work and recognize that he was the man they were looking for to document any future explorations of the gorge it might want to fund. Responding to Fisher, Baker penned a droll rebuttal that he titled "Confessions of a Blood Spattered Demon." In it, Baker asked Fisher for documentation to back up his charges. Nothing solid was forthcoming.

Another challenge came from Gil and Troy Gillenwater, two wealthy Phoenix real estate developers. The brothers had gone on Baker's breakthrough expedition in 1997 as paying clients, and were part of the team that had seen the "hydraulic event" that was later proved to be the great falls. This, they argued, meant that they, too, should be given credit for "discovering" Hidden Falls.

Baker shot back, noting that the Gillenwaters had made their sighting 2,000 feet above the river from a distance of three-quarters of a mile away and suggesting that to equate spotting "mists from a distance" with "discovering" the falls was wrong.

In the end, however, National Geographic acknowledged that the Gillenwaters had "contributed" to the discovery of the waterfall, a resolution Baker called "overly gracious."

One more challenge came from the Chinese, who had mounted an expedition in the gorge at the same time as Baker's. According to Chinese Academy of Sciences geomorphologist Yang Yichou, his 50-member team, not Baker's, was first to the falls, arriving there in October, weeks before Baker. But according to Baker, while Yang and his team did start out ahead of him, they came at the falls from upriver, not downriver, as he had, a route that put them several days behind. No photos of the Chinese expedition at the falls have surfaced, and though the expedition had been intensively covered by Chinese media at the outset, it made its discovery claim only after National Geographic announced Baker's success. The English language China Daily explained the lapse this way: "Although Chinese scientists are surely not short of bravery, rigor and a desire for perfection, they sometimes may be slow to communicate their findings."

Beyond the Waterfall

Baker is happy, as anyone would expect, with a $500,000 book advance and international acclaim as a daring explorer. But the celebrity is not what he was in it for, he says. He is sitting in Tsampa, a dark Tibetan restaurant in Manhattan's East Village on the eve of his return to Katmandu. While he talks, a string of lovely young Tibetan waitresses come over to say hello, putting a sheepish smile on Baker's whiskered, remarkably unweathered face.

"To me this means not just finding a waterfall, but being able to see that waterfall in the profoundly spiritual way that people have sought that waterfall for centuries," he says. "I traveled there as a pilgrim, seeking some kind of transformative, illuminating experience, not just a blank spot to write my name."

But like it or not, his name is now writ large, at least in the United States. Baker fervently hopes he can leave the world stage behind and return to what he calls a life of "blissful obscurity" among his fellow "experience junkies."

He realize that might be wishful thinking.

"Hopefully a lot of them won't know about it," he laughs. "They don't read a lot of newspapers there."

William McGowan is a New York journalist and author of "Only Man Is Vile: The Tragedy of Sri Lanka."

CAPTION: American explorer Ian Baker: "I traveled there as a pilgrim, seeking some kind of transformative, illuminating experience, not just a blank spot to write my name."

CAPTION: Expedition members rope down to the top of the 100-foot-tall Hidden Falls that has eluded explorers for more than a century.

CAPTION: Ian Baker (in mid-expedition) faced some of the most unpassable terrain in the world, not to mention potentially hostile local tribesmen.