The call to prayer sounded just after 3 P.M. It came from a minaret, echoed off the storefronts, and stopped me, briefly, in the middle of the street. All around, people halted their hurrying and turned their attention, momentarily, to God. A few old men pulled cloaks around their shoulders and slipped into the back of a shop. Two boys rushed across the road and disappeared behind a stone wall. A woman picked up her basket of radishes and tiptoed out of sight. Part of me felt odd to be starting a journey into the roots of the Bible in a place so spiritually removed from my own. But continuing toward the center of town, I realized my unease might be a reminder of a truth tucked away in the early verses of Genesis: Abraham was not originally the man he became. He was not an Israelite, he was not a Jew. He was not even a believer in God -- at least initially. He was a traveler, called by some voice not entirely clear that said: Go, head to this land, walk along this route, and trust what you will find.

Within minutes, the afternoon prayers were complete and people returned to the streets. Dogubayazit, in extreme eastern Turkey, was thuddingly bleak, with two asphalt roads intersecting in a neglected town of thirty thousand. Just outside of town, hundreds of empty oil tankers were parked in a double-file line waiting to cross the border into Iran. The trucks, the town, as well as most of the surrounding countryside, were completely overshadowed by a looming triangular peak with a pristine cap of snow.

Mount Ararat is a perfect volcanic pyramid 16,984 feet high, with a junior volcano, Little Ararat, attached to its hip. The highest peak in the Middle East (and the second highest in Europe), Big Ararat is holy to everyone around it. The Turks call it Agri Dagi, the Mountain of Pain. The Kurds call it the Mountain of Fire. Armenians also worship the mountain, which was in their homeland until a brutal war in 1915. I later met an Armenian in Jerusalem who took me into his home, where he had at least 150 representations of the mountain, including rugs, cups, coats of arms, bottles of cognac, and stained-glass windows. Mount Ararat is the first thing he thinks of every morning, he said, and the first thing his children drew when they were young.

I had come for a different reason. Genesis, chapter 8, says that Noah's ark, after seven months on the floodwaters, came to rest on "the mountains of Ararat." Mount Ararat is the first place mentioned in the Bible that can be located with any degree of certainty, and it seemed like a fitting place to begin my effort to reacquaint myself with the biblical stories by retracing the first five books through the desert. The topography of this part of Turkey, which includes the headwaters of the Tigris and Euphrates, permeates the early chapters of Genesis. Chaos, Creation, Eden, and Eve are all drawn from the fertile union of Mesopotamia, "the land between the rivers" and the birthplace of the Bible.

In recent years, however, this region has been one of the most volatile -- and bloody -- in the Middle East. Over forty thousand people have died in a largely overlooked war in which indigenous Kurds have tried to gain autonomy from Iraq, Syria, and Turkey. In every travel book I read about the region the author was at least briefly detained. The Rough Guide I brought actually superimposed a blank area over the region, saying it was too unsafe for its correspondent. "In our opinion, travel is emphatically not recommended." In some cases, it said, security forces respond to the rebellion by "placing local towns under formal curfew or even shooting up the main streets at random."

Though Dogubayazit was calm today, the underlying tension was still apparent. Approaching the center of town, I had barely made it past a string of cheap jewelry stores when a man approached me, eagerly.

"Hello," he said, in English. We shook hands. "You just drove into town in that brown car, didn't you? You're staying in the hotel, in room 104."

The secret police are working overtime, I thought.

"What are you doing here?" he asked.

"Um, I'm here to find out about Noah's ark," I said.

"Noah's ark!" he repeated. "Well, if you want to learn about the ark you have to go to the green building at the end of this street. Go inside and up the stairs until you get to a dark room. Inside there's another set of stairs. Go up those and you'll find another dark room. In there you'll find the man who knows everything about Noah's ark."

At first I thought he was joking, or laying a trap. I thanked him and continued strolling. I had heard enough horror stories -- and seen enough tanks on the road into town -- to ignore directions like these. I walked around for a few minutes, bought some plums in the market, and was heading back to the hotel when I stopped myself: Why exactly had I come here anyway?

Inside the green building I found the sagging staircase and proceeded to the second floor. The room was dark and smelled of discarded cigarettes. I hesitated for a minute, took a step forward, then reconsidered. I was just turning back when I heard a noise from above, then steps. Seconds later a figure appeared. It was a man in his early forties, lean, with black hair and an enormous bushy mustache that cascaded over his lips. His eyes were concealed by the gloom. He appraised me for a second, before saying, in perfect Oxonian English, "May I help you?"

"I was told you know about Noah's ark," I said.

He considered my answer. "But you were supposed to go up the second set of stairs." I agreed.

"Maybe you don't really want to know."

He retreated as quietly as he had appeared and left me standing in the dark. This time I didn't hesitate.

Upstairs, the man was just settling onto a low chair covered with carpets. He gestured for me to sit next to him. Between us was a table covered with books and a handful of photographs. He poured me a glass of tea and we exchanged niceties. He was a native of Dogubayazit, a Kurd. Ten years ago he had served time in prison for his role as an insurgent. He refused to talk about the war and when I asked his name, he gestured toward his mustache: "Everyone calls me Parachute." He was wearing a blue and white horizontal-striped T-shirt that, along with his dark hair, made him look like a Venetian gondolier. After a while I asked if it was possible to climb the mountain.

"It is forbidden," he said. "Since 1991, nobody has been to the top."

"Is there anything to see?"

"If you believe something, you can see. If you don't believe, you cannot see."

"What do you believe?"

"We believe. When we are children, we hear things. They tell us that this is Noah's countryside. Even today, when something happens, the people say that it's the luck of Noah."

"Do you have the luck of Noah?" I asked.

"We know that something is there. We find something there."

"I'm confused. You're saying that you know something that everybody else does not know?"

"Yes." His eyes were big, with deep bags under them. He didn't move at all when he spoke. "I know it's there. I find something there."

"What is it that you found?"

"Ah."

"You won't tell me."

"Hmm."

"When will we hear?"

"One day you'll hear."

"And you'll be famous around the world?"

He crossed his arms in front of his chest in a sly, self-satisfied way.

As Parachute well knew, almost since the Bible first appeared, stories of sightings of Noah's ark have been a staple of Near Eastern lore, making it, in effect, the world's first UFO. Josephus, the first-century historian, wrote of legends that the ark landed "on a mountain in Armenia." In 678 C.E., Saint Jacob, after asking God to show him the ark, fell asleep on the mountain and awoke to find a piece of wood in his arms. By the nineteenth century the sightings grew more elaborate. In 1887, two Persian princes wrote that they saw the ark while on top of the mountain, which is covered in snow year-round. "The bow and stern were clearly in view, but the center was buried in snow. The wood was peculiar, dark reddish in color, almost iron-colored in fact, and seemed very thick. I am very positive that we saw the real ark, though it is over 4,000 years old."

In 1916, two Russian pilots claimed they saw the ark from the air, and the following year Czar Nicholas II sent two expeditions with over 150 personnel to photograph it. Because of the Bolshevik revolution, the photographs never reached him, though his daughter Anastasia is said to have worn a cross made of ark wood. Most photographs of the ark have similarly disappeared, including dozens allegedly taken by pilots during World War II and more taken by the CIA using U-2 spy planes in the 1950s. Even Air Force One is said to have spied the ark. During a flight to Tehran on December 31, 1977, while Jimmy Carter was traveling to a New Year's party given by the shah, passengers on board claimed they saw "a large dark boat." Said UPI photographer Ronald Bennett, who was on the plane: "It's my opinion that the president probably had Air Force One routed over Mt. Ararat and most likely saw the ark too."

Since that time, technology has only heightened interest. Dozens of books have explored the subject, and more than fifty websites track the ongoing chase. In 1988, a stockbroker from San Diego flew a helicopter along the east slope taking photographs. The following year a pilot from Chicago aired footage of an "arklike object" on CNN. Charles Willis, who was once Charles Manson's psychiatrist, ran four expeditions, and astronaut James Irwin, who once took a Turkish flag to the moon in an attempt to butter up the Ankara government, made five. None has found the prize. As my companion and guide, the Israeli archaeologist Avner Goren, had warned, "Archaeologists won't even take into consideration that there are any remains. This story, like Creation, is crystallized from many traditions." But that won't stop the pursuit. When I asked Avner if any of the recent expeditions interested him, he said, "As a scientist, no. But as an adventurer, yes."

Which is exactly what Parachute was banking on. With prodding he explained that during a trip up the north side of the mountain in 1990, with a colleague from England, he found a piece of black wood one hundred feet long. It was located at twelve thousand feet.

"But it could be a hundred years old," I said.

"We tested it."

"And how old is it?"

"When we find out everything, you'll know."

"But why wait? How much money would it take for you to bring me to it?"

He thought for a moment. "It's not the money. It belongs to us. We found the ark. If you give me a million dollars I won't bring you to it. If you wanted the pictures I wouldn't give them to you."

"You have pictures?"

"Yes."

At this point I decided to go back to the hotel and get Avner, who had been napping. Avner had been to the top of the mountain in 1982 on a climbing expedition (no ark sightings, but lots of pure, clean snow). For the rest of the afternoon the three of us sat in Parachute's den. I asked Parachute what explained the ark's appeal.

"The ark is not so interesting to people," he said, "but Noah has meaning, like Mohammed or Jesus."

"You're suggesting that Noah is as important as Jesus?"

"If we can prove that any of these stories happened, then people will believe in God."

"What about you?" I asked. "What did you think when you found it?"

"I was happy. I was walking along -- it was a particularly warm year -- when suddenly I fell into this cavern covered by snow and ice. And there it was."

"I would like to believe your story," I said. "But I find it impossible to believe that in four thousand years you're the first person to go into this hole."

"Around here there are only five guides licensed to go up the mountain," Parachute said. "Two are in jail, one is ill, one won't go. That leaves me."

"Will you show me the pictures?"

He refused.

"What if I tell you that you're being selfish, that there are several billion people in the world who would like to know if Noah's ark exists?"

He didn't react.

"What if I tell you that you could be the savior of the Kurdish people by bringing millions of tourists to this area?"

He didn't move.

"What if I tell you that my mother is dying" -- a lie -- "and that she could die in peace if she knew that Noah was real?"

Nothing.

I was stunned. "Not even for my mother!?" I said. "Do you understand what you have here? More people believe in this book, more people have died because of this book, more people are influenced by this book. . . . You could change the world!"

Parachute was silent for a moment and unfolded his arms for the first time in hours. "You can tell your mother that she can be happy, that in the world there is one person who has seen Noah's ark. The Bible is true."

"So if she sees your ark, will she believe in God?"

"She'll have to," he said. "And you will, too. God is real. I have seen the proof."

Outside, darkness had fallen, and I was a bit unnerved by our conversation. I suggested we take a Turkish bath to decompress. As we walked, I asked Avner what he thought about Parachute's claim. "I suspect he uncovered something," Avner said, "though I don't believe it was the ark." If nothing else, he noted, the chances of finding remains from a five-thousand-year-old wooden boat seemed remote. And yet, now that we were here, the truth seemed far less important. What was important, I realized, was the ongoing hunt, the often-eccentric never-ending quest to verify the biblical story, which itself masked one of the oldest human desires: the need to make contact with God.

Back at the hotel, we picked up some supplies and wandered a few blocks to a run-down, concrete building. Inside we paid a small fee and were ushered into dressing rooms. I stripped off my clothes and wrapped a faded brown dishtowel around my waist. The attendant pointed through several doors, where the musty atmosphere gave way to an empty gray marble sanctuary filled with perfume and steam. The attendant took a bucket of hot water and splashed it over an octagonal platform. I lay down and closed my eyes.

The idea of writing about the Bible had sneaked up on me. Like many of my contemporaries, after leaving home at the end of high school, I lost touch with the religious community I had known as a child. I slowly disengaged from the sticky attachment that comes from a regular cycle of readings, prayers, and services. I separated myself from the texts as well. And ultimately I woke up one morning and realized I had no connection to the Bible. It was a book to me now, one that sat on the shelf above my TV, gathering dust on its gilded pages. The Bible was part of the past -- an old way of learning, a crutch. I wanted to be part of the future. Over more than a decade of living and working abroad I found that ideas and places became more real to me when I experienced them firsthand. It was the opportunity -- and curse -- of being alive in the age of discount airfare.

But even as I traveled, I found that certain feelings from my past kept resurfacing. I sensed there was a conversation going on in the world around me that I wasn't participating in. References would pop up in books or movies that I vaguely understood yet couldn't fully comprehend. I would read entire newspaper articles about wars I couldn't explain. At weddings and funerals the words I heard and recited were just that -- words. They had no meaning to me. No context. They were not part of me in any way. And yet I wanted them to be. Suddenly, almost overnight as I recall, I wanted these words to have meaning again. I wanted to understand them.

No sooner had I made this realization than I discovered how daunting it seemed. For starters, the idea of reading the Bible from cover to cover seemed undoable. The text was too long; its structure too convoluted; its language too remote. I went to the bookstore seeking help, but found instead fifty different translations, with assorted concordances, interpretations, and daily inspirationals. Other options seemed equally unappealing. Though there are shelves of books on every aspect of the Bible -- from spelling to sex -- none seemed to offer what I craved. Were these stories real or made up? When did they take place, and where? Looking further didn't help either. None of the classes I considered tackled these questions. I was left with the book, which sat by my bed for months on end, suffering from renewed neglect. After several years I was no closer to reconnecting to the Bible than I had been at the start.

Then I went to Jerusalem. I had just completed a long project and decided to reward myself with a trip to the Middle East. On my first day in the country I joined an old friend, Fred, who was giving a tour to some high school students. We stopped for lunch on a promenade overlooking the city. "Over there," said Fred, "is Har Homa," a controversial new settlement. "And over there," he said, pointing to the Dome of the Rock, "is the cliff where Abraham went to sacrifice Isaac." Real or not, that piece of information hit me like a bolt of Cecil B. DeMille lightning. It had never occurred to me that that story -- so timeless, so abstract -- might have happened in a place that was identifiable, no less one I could visit. It had never occurred to me that the story was so concrete, so connected to the ground. To here. To now.

In subsequent weeks I had the same experience in a variety of places -- the Dead Sea, Petra, the Pyramids. In the Middle East, I realized, the Bible is not some abstraction, nor some book gathering dust. It's a living, breathing entity unencumbered by the sterilization of time. If anything, it's an ongoing narrative: stories that begin in the sand, get entrenched in stone, pass down through families, and play themselves out in the lives of residents and visitors who traverse its lines nearly five thousand years after they were first etched into memory. That was the Bible I wanted to know, and almost immediately I realized that the only way to find it was to walk along those lines myself. I would take this ancient book, the embodiment of old-fashioned knowledge, and approach it with contemporary methods of learning -- traveling, talking, experiencing. In other words, I would enter the Bible as if it were any other world and seek to become a part of it. Once inside, I would walk in its footsteps, live in its canyons, meet its characters, and ask its questions in an effort to understand why its stories had become so timeless and, despite years of neglect, once again so vitally important to me.

At first, few people thought this was a good idea. I returned home and tried to put it out of my mind, but couldn't. A few months later I traveled back to Jerusalem, and on my first day went to visit Avraham Biran, the dean of biblical archaeologists and the colleague of a friend. Professor Biran listened attentively to my ramblings. He squinted at me from behind clouds of cigarette smoke. And when I finished, he leaned across his desk and told me politely that I was out of my mind. There were few confirmed sites. Most sites that did exist were in war zones. And most were supervised by archaeologists who were far too busy to explain them to me. "It really would be an imposition," he said. I sat back, deflated.

But even as he discouraged me, Professor Biran could not resist reaching out his hand. Over the next two hours, he plucked photographs from his desk, pulled books off his shelf, and eventually took me to the maws of his laboratory to show me some shards of pottery. That night he called me at home. "What you need is someone to go with you," he said, "someone who has a sense of poetry. Somebody like Avner Goren." Several days later, in the Negev, I ran into two young Israeli guides and discussed my plan with them. "What you need is someone like Avner Goren," they said.

Two days later I telephoned Avner at his home in Jerusalem. He agreed to pick me up the following morning and arrived at dawn in a rickety blue Subaru. In his fifties, with a body that reminded me of Winnie the Pooh's, he had squinty blue eyes, bulbous cheeks, a boyish grin, and curly hair. Though he was dressed in standard Israeli fare -- blue jeans, T-shirt, and sandals -- that morning his most dashing feature was a long white scarf, Lawrence on his way to Arabia but still clinging to Oxford. After greeting me warmly, he drove around the corner to a coffee shop in the fashionable German Colony where we chatted over herbal tea and croissants -- instant neighbors in the global bistro.

A charming, charismatic figure, Avner was a romantic, a child of the desert. For the fifteen years that Israel controlled the Sinai -- 1967 to 1982 -- he was the region's chief archaeologist and preserver of antiquities. But soon after, he abandoned the academy to become a popularizer of biblical history, one of Israel's most eloquent spokesmen on life in the ancient world. He tutored prospective Israeli and Palestinian guides, gave lectures on ancient history around the world (for the State of Israel, the UN, and others), and was a charter member of a pioneering group of Israeli, Jordanian, and Palestinian educators who were using archaeology to open the fabled Nabatean Spice Trail to cross-border traffic. Indiana Jones, meet Dag Hammarskjöld.

As we talked, a sort of implicit teacher-pupil relationship developed. "I was thinking about which route in the Sinai to take," I said. Avner didn't flinch. "I prefer the southern route," he said. "It offers the best experience." "I'm concerned that I won't be able to get to certain sites in Egypt," I said. "Fear not," Avner said, rubbing his fingers together in the international expression for an exchange of money. Finally, after tiptoeing through this logistical minefield, I told him about my conversation with Professor Biran. "Half the people I meet tell me I'm out of my mind," I said. "They tell me it can't be done." As I finished a smile slowly crept across his face. "I don't think you're crazy at all," he said. "I think it sounds exciting."

I sat back, relieved and exhilarated. "Somehow I knew you would," I said. "By the way, would you come along?"

A year passed between that meeting in Jerusalem and our first foray into the field, in Turkey. During that time I returned to the United States and set about preparing myself for the trip. First I read the Bible, chapter by chapter, verse by verse. It took me almost a month, and I was amazed by how little I remembered. Abraham went to Egypt? Moses committed murder? What were all those rebellions in the desert? I began making a chart linking places in the text to places on the ground. Was Abraham born in Iraq or Turkey? Where was Mount Sinai? Was there really a place called Sodom? This process led me to read about what those places would have been like at the time the stories were written. I started with books on history, archaeology, geography. These were rational subjects, consistent with my past as an undergraduate history major, as a master's student in international relations. Keep it real, keep it concrete, keep it safely removed from spirituality. "This is a literary quest," I kept telling myself. "This is about me and the Bible. This is not about me and God."

As I bounced from topic to topic I realized how little I knew about the ancient world. Books about history led to ones about religion; religion books led to language books; language to culture. In time, the topics became more obscure. I found myself scouring used bookstores for volumes on desert botany, pyramid construction, Babylonian creation stories. I even bought a book called The Bible and Flying Saucers: The Miraculous Truth, which included the cover line "The messengers are here!"

The homework itself became part of the adventure. My chart became more and more complex. One bookshelf filled up, and I bought another. My friends wondered about this new obsession. Why was I sprinkling conversations with references to African quail migration or the biological roots of manna? Why did I want a six-volume, 7,035-page reference book for my birthday? "Not to worry," I assured them. "I'm not becoming a nut." And I believed it, too. This was about history, I assured myself, this was about grounding the text in reality. "I'm giving myself a master's degree in the history of the Bible," I said. What could be more fun, or more rational?

For all of my reading, however, the moment I met Avner at the Tel Aviv airport for our trip to Turkey, I realized that my education hadn't even begun. I was dressed in a neatly pressed shirt from Banana Republic with a bag full of books and a new pair of hiking boots. Avner, meanwhile, was nearly spilling out of his T-shirt, beltless baggy trousers made by some bedouin in Sinai, and fifteen-year-old scruffy sandals. The message was clear: My learning was all in my head; Avner's was all in his feet. I had never met a man who knew so much who carried his knowledge so lightly. He knew all the languages of the biblical route -- Hebrew, Arabic, Turkish -- as well as a few others -- English, Greek, and hieroglyphics. He had not only several bookcases full of Bible books but several rooms. Yet he was unassuming to the point of being bashful. At times this frustrated me -- why didn't he speak up when we ran into a pontificator? But eventually I realized that Avner, in his way, was like the place he idolized. From afar the desert might seem distant and reserved; draw closer and it has a great story to tell.

Avner was like the desert in another way: He seemed completely removed from the modern world. For all his clarity of mind, he was conspicuously disorganized, with more twisted pieces of paper, bent paper clips, and stale pieces of chocolate spilling from his pockets than anyone I ever met. His car was like an archaeological site, with layer upon layer of his life piled up in the backseat. He rarely returned messages. He often forgot where he was going. And he never met me for a trip having not stayed up overnight to pack. Even then, we usually had to go back for his passport. His appearance, which rarely varied from that morning at the airport, reflects this personality. He owns only one tie, which he keeps knotted under his bed. He once addressed a UNESCO conference in Paris wearing hiking boots. And when, late in our journey, his daughter, Smadar, got married, Avner had to buy his first pair of dress shoes.

There was another way in which Avner was a paradox. For all his learning, for all his stature and international acclaim, he had never bothered to finish graduate school. He was too drawn by the opportunity to give a speech, to join a crusade -- to go on a trip with someone like me. Remarkably, this blemish did little to stunt his success. If anything it was a testament to his talent that he continued to rise in intellectual circles despite not having the one credential that would seem to be necessary. He was a fellow at the prestigious Albright Institute of Archaeological Research in Israel. He was recruited for prominent digs. He counseled prime ministers. And he knew everyone within a thousand-mile radius of Jerusalem. I never produced a name of someone I wanted to meet -- an artist, a scientist, a bedouin, a scholar -- whom Avner couldn't deliver within twenty-four hours. And I never attended a meeting with one of those individuals in which the other person, regardless of stature, didn't defer to Avner. As a friend of his told me, "Avner Goren is like Moses. He's a prophet. He has no boundaries, no borders, he's actually part of the land. And the best thing is, he doesn't even realize it."

This set up the unusual equation at the heart of our experience. I wasn't looking for a father any more than Avner was looking for a son (he has one). I wasn't looking for a prophet any more than he was looking for a disciple. And yet, we both were looking for the Bible, which, at the moment, had brought us together at the start of a journey that was still hardly defined.

It was just after 5:30 on our first morning in Turkey when I joined Avner outside our hotel in Gaziantep. The street lamps, at this hour, were still flickering orange. The smells of dawn -- cinnamon, cardamom, a whiff of burnt sugar -- were just starting to emerge. We had decided to begin our trip by trying to catch sunrise on the Euphrates, before proceeding eastward to the Tigris and the two-day trek through the Turkish highlands to Dogubayazit. We nodded our good mornings with Sait, our driver, and buckled in for the ride. Since meeting him the previous day, Sait's unflappable personality (along with the occasional pack of cigarettes) had helped ease our way through the numerous checkpoints where authorities prodded our passports, our luggage, our bodies, or all three.

Once we were out of town, the air grew agitated, until suddenly a crack of lightning careened across the sky. The flash was followed by another, and the two jolts ignited a series of awakenings. First the sky began to lighten, revealing a clog of slate gray clouds. Then the ground emerged, exposing a flat landscape of pale, spent grass. Gradually other life-forms appeared -- groves of young pistachio trees, a stretch of tufting cotton bushes. A turtle crossed the road.

Minutes later we sped past an open floodgate, parked, and ambled down the rocky bank. Large boulders huddled at river's edge, with pebbles trickling into water the color of mint. A woman in a black bedouin dress tiptoed down the embankment carrying a teakettle. The current was swift in the middle of the river, but the edges were smooth like gelatin. From here, the river picks up strength as it passes through Syria and into Iraq, before merging with the Tigris near the Persian Gulf.

By the time we slipped our toes into the water, the sky was light but the sun was still hidden. For a few moments we watched it try to burn through the clouds. Occasionally a ray would peek through, only to be blotted out again. The struggle continued for half an hour, with the sun angling to penetrate the shield, reaching, stretching, and giving off the most storybook sunburst, which was all the more remarkable, since its source was veiled. Finally, at a few minutes past seven, the sun prevailed. Because of its ordeal, it had lost any romantic qualities by the time it slid free. It wasn't orange or red or even yellow, like most morning suns. It wasn't tender at all. It was clear, round, and white.

It was day.

The ride east from the Euphrates started out painless. Compared to the European part of Turkey, with its soaring pines and castles, the Asian part is flat and dusty. In late summer, the fields were blotted with green, but cautiously, as if the crops might sag back into the sand. The main reason was the fickle supply of water, which is ferried across the fields by a ramshackle network of gutters and concrete entrails. At one point we stopped by a roadside gathering, where a boy playing on one of those aqueducts had just been swept to his death. The previous week, a woman said, there had been no water at all.

As we drove we began to discuss the importance of water in the ancient world. In the history of humanity, civilization came relatively late. During most of their time on earth, humans roamed in migrant bands that hunted and foraged for food. This period, the Old Stone Age, began around three million years ago and continued until approximately 15,000 B.C.E. A Middle Stone Age, with communal living, continued for roughly another five thousand years. The bigger change, what Avner called "the most important revolution in history," occurred around 9000 B.C.E. with the advent of agriculture. That change was centered in Mesopotamia, in the area of present-day Turkey and Iraq, where local populations began experimenting with cultivating wheat and barley. As cultivation proved successful, farmers began looking for ways to expand production in order to feed more people. To do that, they needed reliable irrigation, which led them to tap their greatest resource: the Tigris and Euphrates.

What the rivers provided was a regular supply of water and, more important, an annual inundation that covered the desert with arable soil. The floods of Mesopotamia and Egypt were so unusual in an otherwise arid region that, coupled with the rain-fed mountains in today's Syria and Israel, they formed the incubator of civilization, the Fertile Crescent, a cradle of productivity in a sea of sand. In particular, rivers gave people the incentive to stay in one place and organize themselves -- to dig canals, bake bricks, build plows. "Just imagine you have a canal in your area," Avner said. "You have to clean it; you have to maintain it; but you never enjoy the water. It flows to a place that's twenty days away on a donkey. So you take care of the water for people you'll never meet; and somebody else takes care of yours."

With thousands of canals serving tens of thousands of people, the only way to maintain this growing network was to develop an equally elaborate system of laws, schools, trade. Civilization. "Soon enough, individual civilizations started fighting," Avner said. "To survive, the victorious states started annexing their neighbors." Empires were born. The first such empire -- Sumer, in lower Mesopotamia -- was quickly shadowed by ones in Akkad and Assyria, also in Mesopotamia, and ultimately one in Egypt. The inevitable clash of these titans created a combustion that would make the Fertile Crescent an unprecedented engine of creativity, giving birth to the world's first epic poetry, legal code, religious proverbs, and written word. In time, it also gave birth to a written document that would prove to be an even greater generator of culture.

By late afternoon, we had crossed the floodplain and begun our descent to the Kurdish stronghold of Diyarbakir. One of the oldest cities on earth, Diyarbakir dates back five thousand years and was controlled at times by the Assyrians, Persians, and Alexander the Great of Greece. The Romans built a huge city wall of basalt, which in turn was rebuilt by the Byzantines, who nicknamed the place "The Black." Residents boast that the circular five-mile wall, along with the Great Wall of China, is one of two man-made objects visible from space.

For all its past greatness, the town is chokingly grim today, a mix of concrete buildings around a dilapidated town core. With half a million residents, Diyarbakir boasts a handful of impressive mosques and a market selling carpets, spices, and Medusa-like shags of cheap belts. On this day, the heat baked the bananas and garlicky meat, mixing them with diesel exhaust into a noxious perfume. The one source of delight, and good aroma, was the hundreds of plump watermelons spilled from every flat surface. Sprung from the Tigris and fertilized by pigeon droppings, the fruit is the town's trademark. This week a watermelon festival was under way. Driving into town, we passed a fifty-foot obelisk with a giant, papier-mâché watermelon impaled on top; it reminded me of a Claes Oldenburg sculpture of an olive on a toothpick.

We dropped our bags at our hotel and headed down to the river. The Tigris was narrower here than the Euphrates, and murkier. The muddy banks were lined with reeds. Underneath a stone bridge, a group of adolescent boys splashed in their underwear while an older boy watered a cluster of cows. Nearing six o'clock, there was almost no light on the river; the sky was the color of sludge. Nearby a man tossed a net into the current and pulled it out with a bamboo pole, spilling mullet onto the mud. We sat on a boulder for a few minutes until Avner reached in his knapsack and pulled out a book with a royal blue cover. "Shall we?" he said.

As he flipped to the page I grabbed for my copy, the same one that had sat by my bed for years. I was nervous. This was our first chance to test one of the central ideas behind our trip. In addition to retracing the first five books of the Bible, also called the Five Books of Moses, we planned to read the stories in the locations where they took place. Still a newcomer to the text, I hoped this effort might deepen my appreciation of the stories by freeing them from their covers and replanting them in the ground. For Avner, it would be an attempt to revisit the stories in light of a lifetime of learning. But the truth was, neither of us quite knew what to expect.

"Listen to the words closely," he said. "Listen for the sound of the rivers: 'When God began to create the heaven and the earth, the earth was unformed and void.' " These words suggest a vast emptiness, Avner noted, but the next line is more evocative: "And darkness was upon the face of the deep." "In Hebrew," he said, "the word for deep is tehom, which means chaos. In Mesopotamia, chaos was represented by a sea monster, Tiamat. Tiamat is the root for tehom. We're only in the second line of Genesis, and already we have a direct link to the cult of water in Mesopotamia."

We continued reading. For the next chapter and a half, the Bible tells the story of how God created the world. On the first day God creates light and dark. On the second day he generates an amorphous mass, "an expanse in the midst of the water," and also forms the sky. On the third day he divides this expanse into the earth and seas and brings forth vegetation. On the fourth day he creates the sun and the stars; on the fifth, birds and sea creatures; on the sixth, cattle and animals that creep. Also, on the sixth day God, using the plural, announces, "Let us make man in our image, after our likeness," and creates an unnamed male and female. Finally, on the seventh day, having "finished" his work, God declares the day holy and rests.

In many ways, this story, which appears without preamble at the beginning of Genesis, seems completely removed from time and place. But in other ways, the story is deeply rooted in a particular time -- the second and third millennia B.C.E. -- and in a particular place, Mesopotamia. Specifically, Genesis draws on the Mesopotamian obsession with water. Considering the importance of rivers, it was inevitable that water would play a vital role in ancient creation stories. The unanimity across cultures, though, is striking. The earliest stories date from the third millennium B.C.E. and come from Sumer, in today's southern Iraq. Living in an area the size of New Hampshire, the Sumerians generated a vast literary outpouring: Over forty thousand lines of Sumerian script have been found, compared with twenty-three thousand lines of biblical script. The root of the Sumerian worldview was a primeval sea, which split into a vaulted heaven and a flat earth, an idea almost identical to that of Genesis. The Sumerian universe was controlled by humanlike gods, the most important of whom was Enki, the god of water, who created light, plants, animals, and humans.

The Babylonian creation story, also from Mesopotamia, is even closer to Genesis. In the story, the world is presented as a watery chaos, represented by the monster Tiamat. During a rebellion, another god, Marduk, slays Tiamat and slices her carcass in two, creating heaven and earth. After his triumph, Marduk proceeds to create, in succession, light, the firmament, dry land, heavenly lights, animals, and man. Afterward he rests and celebrates.

"So you see," Avner said, "in both stories, water precedes everything, a struggle ensues, and everything else emerges from that."

"But when Westerners imagine God creating the world," I said, "they don't imagine a struggle."

"Yes, but the struggle is still there," he said. "The Bible states very clearly, 'And God says, "Let there be light." And there was light. And God saw the light: that it was good.' Here you have the start of good things and bad things. On the third day God says twice that something is good. There is clearly an echo of struggle here, getting rid of evil."

"So how did that echo get there?" I asked. "The biblical story was written down in the first millennium B.C.E. These stories come from the third millennium."

"Ah. That's the story of the Bible. Though it was written down later, large parts of it consist of oral traditions that were passed down for hundreds of years, many with the same words. The Bible, like The Iliad, combines large amounts of ancient texts."

In the story of Adam and Eve, for example, ideas like the tree of life, the snake, and man being made from clay were well known in Mesopotamia. The name Eve is derived from a Sumerian pun on the word for rib. Even the Garden of Eden has ancient roots. In one prototype, the god Enki summons water from the ground to create a garden, which the mother-goddess fills with plants. When Enki eats these plants without permission he is ostracized and cursed to die. In the story, the garden is located "east of Sumer."

Genesis also places its garden "eastward, in Eden" and begins with a watering: "There went up a mist from the earth and watered the whole face of the ground." The Bible seems to place Eden near Sumer specifically, saying the garden is located at the junction of four rivers. One of those rivers is the Euphrates, another the Tigris. Though we are only in the second chapter, and clearly in the realm of allegory, already the Bible is rooting itself firmly in the ground, in actual places, in geography. The stories seem to be reaching out, saying: These are not mere tales -- this is not recreation -- these words are as indispensable to you as the landscape, the soil, even water itself. Stories, like rivers, give life.

"All of which raises a question," I suggested. The light was mostly gone by now and a green haze had settled over the bank. The cows had wandered away, leaving only a stir of mosquitoes. "If these stories draw so heavily from Mesopotamia, how are they different?"

Avner removed his glasses and smiled, as if he had been waiting for this. "The difference is God," he said. "He's much more abstract. There's no biography, no mythology. He just appears and begins to create the world, using only words as tools. Yet from the beginning, he's solely in control -- at least of nature. His ability to control man is much less complete."

The next morning we headed out early for a two-day drive into the highlands. Quickly the terrain began to change. The congestion of Diyarbakir faded, giving way to pastoral surroundings that seemed to grow more antiquated as we climbed higher. The roads deteriorated and mud houses appeared, with sheaths of tan-colored sesame on the roof. Turkeys scurried in the yards, where men on stools played backgammon. Women with black veils, balancing baskets of zucchini on their heads, dotted the roadside.

Eventually our conversation turned as well. With so much focus on rivers, it was only natural that ancient storytellers fixate on one notable side effect: floods. The Bible gets to this almost immediately, in the sixth chapter of Genesis. After telling the story of the Garden of Eden, the text outlines the successive generations that lead from Adam and Eve to all humanity. Eight generations into this line, Lamech gives birth to a son, Noah, who in turn gives birth to three sons of his own. Around this time, God sees how wicked and lawless mankind has become and announces, "I will blot out from the earth the men whom I created," for "I regret that I made them." But Noah finds favor with God, because he is a "righteous man."

God tells Noah to build an ark out of gopherwood, lined with pitch and divided into three separate decks, which he should fill with seven pairs of "clean" animals, presumably kosher animals like chickens, cows, and fish, and one pair of every other animal. He also takes along his own family. In the six-hundredth year of Noah's life, the fountains of the deep burst apart, the floodgates of the sky break open, and it rains for forty days and nights, until the highest mountains everywhere are covered in water and "all the flesh on earth" is killed.

After seven months on the water, the ark comes to rest on "the mountains of Ararat," where it sits for another three months until the tops of the mountains become visible. Another month passes and Noah sends out a raven, which flies around until the waters have dried from the earth. Then Noah sends a dove, which is unable to find a resting spot, suggesting that water still covers the ground. Noah sends the dove again seven days later, and it returns with an olive branch, a sure sign of life. A month later, Noah removes the covering of the ark, goes ashore with his family, and sets the animals free.

As with Creation, the story of Noah fits into an extensive tradition. Flood stories appear in 217 cultures around the world, according to authors Charles Sellier and David Balsiger. Ninety-five percent of these stories talk about a global flood, Sellier and Balsiger note, 73 percent say animals and a boat were involved, and 35 percent claim a bird was sent out at the end. Babylonian flood stories seem directly connected. In the story of Gilgamesh, Enki warns the hero, Utnapishtim, about a flood sent to destroy humanity and orders him to build a cubical ship. After a seven-day flood, the ship comes to rest atop a mountain and a bird is set free. The Babylonian stories also share a thematic parallel with the Bible. Both stories represent a shift away from mythology and toward history, with names, dates, and biological ages. As Avner noted, Noah is the father of a new generation and the Flood is another example of land emerging from a watery chaos, a second creation.

Beyond its literary roots, the story of Noah's ark begins another, more fascinating side of exploring the Bible today: namely, the race to prove that it happened. Some explorers have claimed they found the "real" Garden of Eden, but even the most credulous Bible enthusiasts believe those efforts are probably fantastical. With Noah, though, and the introduction of historical details, these efforts begin to gain credibility. They reach the point of hysteria with attempts to authenticate later passages like the ten plagues, the splitting of the Red Sea, and Moses' receiving of the Ten Commandments on Mount Sinai. Almost every day of our journey we would encounter another of these enthusiasts, and in time I came to marvel that in addition to creating communities of believers, the Bible had created equally passionate communities devoted to the arcane, quasi-scientific analysis of, say, whether the zebras would have been on the second deck of Noah's ark next to the lions, or on the third deck next to the koala bears. I marveled even more when I got caught up in the same questions.

The story of the Flood has provided a mother lode for such speculation. In the summer of 1929, the English archaeologist Leonard Woolley was digging in the Sumerian capital of Ur when his workers came across a provocative find: a deep stratum of Euphrates silt poised between two layers of civilization. Titillated, Woolley, a former intelligence officer with a flair for the dramatic, lowered himself thirty feet into the ground and that afternoon issued a telegram: "We have found the Flood!" The news electrified the press and intrigued scientists. "We all agree that your theory is mad," one colleague said. "The problem which divides us is this: Is it sufficiently crazy to be right?" Within days even Woolley had to concede that it wasn't, as excavations proved that it was a localized flood. "It was not a universal deluge," he wrote.

But the bait had been laid, and generations of scholars have been unable to resist lowering themselves in after it. One question: Where did all the water come from? Some have said underwater volcanoes, others melting glaciers. Because the text says the forty days of water came from above and below, a few hydrologists have suggested a vapor canopy may have enveloped the earth. (One side benefit of the vapor: It would have blocked ultraviolet rays, thereby helping Noah live six hundred years.) Many have tried to date the Flood. Two oceanographers recently suggested the Mediterranean may have flooded around 5600 B.C.E. Woolley himself placed the event around 2800 B.C.E. But Gene Faulstich, founder of something called the Chronology Research Institute in Iowa, puts them to shame. Using astronomical dating, he says the Flood occurred on May 14, 2345 B.C.E. It was, he says, a Sunday.

If the Flood has been grounds for speculation, the ark has been ripe for obsession. The Bible says the ark should be three hundred cubits long, fifty wide, and thirty high. A cubit is the length of a forearm from the elbow to the tip of the middle finger. Using eighteen inches as a standard, the ark would have been roughly the size of a soccer field, four stories high. That would make the ark, built without metal, five times longer than the Mayflower and, notably, half as long as the Titanic. Though most scholars, including Avner, consider the numbers in the Bible to be idealized, such thinking has not deterred enthusiasts. One problem has been that since the world has over one million species of animals today, how could they fit onto one boat? In The Genesis Flood, John Witcomb, a theologian, suggests that with common ancestry Noah would have needed no more than 3,700 mammals, 8,600 birds, and 6,300 reptiles, which would have been fine considering volumetric analysis shows the ark could have held up to 100,000 sheep.

But could one family of eight possibly have tended all these animals? That, too, is no problem, says Ken Cumming, a biologist: Many of the animals would have responded to the lack of light by going into hibernation. Even if the animals could have fit and been cared for, could they have been housed in a food-chain-proof way? Easily, says Eddie Atkinson, a reverend and amateur ark-builder: Birds and rodents would have been on the top deck; lions and tigers on one end of the second deck, hippos and rhinos on the other, elephants and giraffes in between. The bottom deck, analysts assert, must have been empty, because according to zoologists at the San Diego Zoo, during their year aboard the ark the animals would have generated eight hundred tons of manure.

By our second day the drive had become downright eerie. All through Turkey the scenery had been pastoral, but hardly otherworldly. Now, six thousand feet above sea level, with an almost complete absence of agriculture, we were entering a palette ripe for mythology -- and conflict. Tanks were parked every mile along the highway, with soldiers sitting in front on white plastic lawn chairs. A giant billboard said, in Turkish and English, HOMELAND ABOVE ALL, and in the road signs that show people crossing the road, the people were dressed in traditional costumes.

Most unnerving was the topography itself. The hillside plateaus were covered for miles in basalt coated in pale green fungus that looked like mold growing on charcoal. The basalt, while cooling from a volcanic eruption, had splintered into hundreds of fists, which in turn had splintered into jagged fingers that reached to the sky for relief. Altogether, the formations reminded me of those pictures of bodies frozen, gasping, in the aftermath of an atomic bomb.

As we drove, Avner had been playing with a toy that some friends had given him, a portable Global Positioning System, or GPS, device that tracked our route using military satellites. For several hours he had squirreled himself away in the back, frantically pressing buttons, trying to figure out how to program it. Just before noon he leaned forward, tapped me on the shoulder, and pointed out the window. "Look!" Sait jerked to a stop and through a break in the cliffs, fifty miles ahead and thousands of feet higher than anything around it, was the pure triangular crest of a mountain, like Mount Fuji with its solemn mien. And at that moment I had the first chilling intimation of what walking the Bible might bring. Genesis does not give details about where the ark lands. The Bible may not want us to know. But if a flood did cover the earth, if an ark survived that flood, and if that ark settled on a spot where land first appeared, there was little doubt in my mind that it would have landed here. And for me it was stunning confirmation that the Bible may or may not be true, it may or may not be historical, but it is undoubtedly still alive.

The following morning, after our meeting with Parachute, we turned south for the final portion of this trip. Our first destination was Sanliurfa, a Turkish town not far from the border with Syria that for thousands of years has been associated with the great patriarch of monotheism. Considering his importance, Abraham seems to appear out of nowhere in the Bible. After the Flood, Genesis recites the generations that follow Noah, then relates another story with Near Eastern roots, the tower of Babel. The story begins by asserting the unity of the world: "All the earth had the same language and the same words." The descendants of Noah then begin to settle in the "land of Shinar," the biblical name for Sumer. In an echo of the agricultural revolution, the men decide to make bricks for themselves, then to build a communal monument. "Come, let us build us a city," they say, "and a tower with its top in the sky, to make a name for ourselves; else we shall be scattered all over the world."

God sees the city and decides to frustrate their plans, declaring, "Let us, then, go down and confound their speech there, so that they shall not understand one another's speech." God then scatters the builders "over the face of the whole earth." The doomed tower came to be called Babel, the Bible says, from the Hebrew word for "confuse."

Following this story, the text outlines the ten generations that lead directly from Noah to Abram. According to Genesis 11, Abram, which means "the father is exalted"(he would later change it to Abraham, "father of a multitude"), was born in Ur of the Chaldeans where he took a wife, Sarai, before leaving for Canaan. The term Chaldeans is believed to refer to a later settlement, around 1100 B.C.E., and was probably added to the story when it was written down. The term Ur, by contrast, has tantalizing ancient parallels and suggests biblical storytellers wanted their bloodlines placed deeply in Mesopotamia. The city of Ur was the capital of Sumer and one of the grandest cities of antiquity. Built around a stepped temple, or ziggurat, believed to have inspired the Tower of Babel, the city squeezed two hundred thousand citizens into labyrinthine quarters.

Like most Babylonian cities, Ur was surrounded by satellite settlements of farmers or shepherds. At times the two groups clashed, as when farmers wanted to grow crops in the marshland and shepherds wanted to graze sheep. The Bible echoes this struggle when it makes Adam and Eve's first child, Cain, a farmer, and their second, Abel, a shepherd. When God expresses favor for Abel, Cain murders his sheep-herding brother. Abraham was probably a shepherd, too. He likely would have lived outside of Ur, but later moved during a period of drought, tension, or economic change. He and his clan would have gone to another city, perhaps stayed five or ten years, then moved again, most likely in a northwesterly direction, until they arrived in Harran, a well-known ancient crossroads. This type of migration happened throughout the third millennium B.C.E., except for a period of economic collapse around 2000 B.C.E. According to scholars, Abraham was likely born near the end of that downturn, around 1900 B.C.E. To be sure, no evidence exists that Abraham -- or any other central character in the Five Books -- lived during this period. By contrast, much evidence suggests that Abraham is a compendium -- a crystallization, to use Avner's word - - of many oral traditions. But one thing is clear: The story is uncannily realistic to the history of the area. As Avner said, "It could be true."

This air of authenticity is one reason the story has persevered. All through our drive to Sanliurfa, we saw living details -- sheep, shepherds, dust, robes. It became like a game of "I Spy." There's a donkey: "Abraham's transportation!" After a while we became so preoccupied that we didn't even notice when Sait went speeding through a roundabout and suddenly got motioned over by the police. Instantly, our worst fears returned. An officer in a crisp blue uniform came to the window and asked Sait to step outside. As he did, Avner and I hid our equipment and placed a sign from the tourist authority on the dashboard. The officer was joined by another. A green army jeep sped up, followed by a motorcycle. We got out of the car. Suddenly there were five different officials, each wearing a different uniform, prodding our car, our passports, our GPS device. The men seemed like unshaven boys playing grown-up in a quiet war. "It's almost a police state," Avner whispered.

Finally a car pulled up and a plainclothes officer in a black suit spoke to the men in the reverse order in which they had arrived. He examined the situation, the car, us. He spoke with Sait. And then, just as quickly as the tension had mounted, he defused it. He shook our hands and gestured for us to proceed. Before we did, Sait began clearing the backseat of our bags and maps and in plopped a teenage boy. Our penance was to give him a ride. "Probably the son of the cop," Avner mused.

But he turned out to be more than that. Yusuf, eighteen, was studying to be an English teacher. Though he was dressed in ratty jeans and a scruffy T-shirt, his hair was neatly combed over his ears. He offered to take us on a tour -- part of the scam? -- but insisted he didn't want to be paid. He directed us toward the center of town.