ADDIS ABABA—I can’t tell what my dread means. Shrieking children chase one another around the Ethiopian swimming pool. Tanned, well-oiled U.N.-types lumber up and down the lap lanes. The hotel pool’s chlorinated oblivion mirrors my unease, or maybe my exhaustion. I didn’t sleep last night on the overnight flight from Rome to Addis Ababa. Usually, I find such arrivals thrilling. I relish the anonymity of knowing no one and of no one knowing me. Sitting by the largest swimming pool in one of the world’s poorest countries, I feel remorse at having come. It costs $20 to occupy the white, cement deck; another $25 for the Jessica Simpson-brand flowered two-piece I purchased in the gift shop.

The children sound like ominous birds, maybe flesh eaters. I can’t tell the difference between diplomats and arms dealers. This sinister foreign tableau reminds me of the landscape of the young Joan Didion. If she came to Addis Ababa, she’d visit this pool too. She, however, would be clad in a chic black suit and her cool reserve. Sweating and vainly burning in an ill-fitting tankini, I am the opposite. I am hopelessly overexposed.

Chemical waves lap at my fellow First Worlders. I will this time to pass. At sunset, my friend José Cendón, a Spanish photographer based here, will arrive. I haven’t seen him since we worked together in the Somali capitol of Mogadishu two years ago. On his next trip to Somalia, in November 2008, Cendón was kidnapped by pirates and held for three months. We’ve Skyped and e-mailed since his release, but there’s always the awkward, electronic delay. Waiting for dark, I lie prone. Outside the green, plastic perimeter, the country withers.

Not all of it, though. Ethiopia has already proved to be a different land than that of Ryszard Kapuscinski’s The Emperor, in which the Polish poet and journalist chronicles the courtly intrigues of Ethiopia’s last king of kings, Haile Selassie. Ethiopia is also a far more complex place than stock images of starving children. The road from the airport to my guesthouse is lined with half-built high-rises. Rebar, like the spines of prehistoric animals, sprouts from their frames. There’s a construction boom. In the airport when I arrived, there were at least 20 Chinese men ahead of me in the visa line. They spoke neither the Ethiopian language of Amharic nor English. Unlike most tourists, they didn’t look around, only at the tight cluster of one another. The Chinese are building most of Ethiopia’s new roads. They bring workers from China to do the labor, which irritates many Ethiopians. I studied the arrivals board to see if I could discern where in China they’d come from. The place name meant nothing to me.

The terrible traffic also signifies the capital’s boomtown status. From the airport, after a rush-hour jam this morning, I finally reached my guesthouse. This is the neighborhood Cendón told me to stay in. The neighborhood doesn’t really exist yet. There is no road, just a track through what look to be sand dunes. The building is more Saudi sheik—pastel-colored, tinted windows—than African. Inside, the living-room walls are dotted with photographs of Americans who’ve come to adopt babies. All the other guestrooms are full with eager, prospective parents.

In truth, the guesthouse is dismal. We have to share the bathroom. But it received such glowing reviews on TripAdvisor.com. Of course, I think, this is where the new parents had one of the happiest days of their lives: They were given children. As an outsider, I find the sheer numbers of pictures of children and of potential parents disturbing. It seems like an industry. From my room, I can hear one frustrated father arguing with his new son. I start writing. “The Addis Ababa Hotels Are Booked With American Parents”:

I wake from a nap to hear a child too old

to forget his first parents scream mama, aba

in the next room. Instead of their coming,

I hear his new father yank open

the pressure-board door,

growl Stop it in a language I,

but not the child, can understand.

The tone is clear enough to shudder

the cheap wall between us. Stop,

the father softens, adding, please.

These walls are tissue-thin, but never mind. I won’t be in the capital for long. Before dawn tomorrow, I’ll board a flight to the north. Ethiopia is also a tourist destination, and this trip is a vacation. It’s a gift to myself for finishing seven years of work on The Tenth Parallel, the account of a faith-based fault line where Christianity and Islam collide here in Africa and, to the east, in Asia. This horizontal band runs between the equator and the line of latitude 700 miles north, the 10th parallel. Four out of five of the world’s 1.6 billion Muslims live outside the Middle East. They aren’t Arabs; they’re Africans and Asians. Along this fault line, they meet nearly half of the world’s 2 billion Christians. (For more on the 10th parallel and the nations that surround it, see this interactive map produced by the New American Foundation.)

This is the band where religious fervor and swelling populations are growing faster than anywhere else in the world. This is the band where the world as we know it is breaking apart. This is the band that runs through Ethiopia. Today, Ethiopia’s population of nearly 83 million is divided nearly evenly between Christians and Muslims. I’ve come to see what happens when the two religions meet.

It’s hardly a new encounter. Ethiopia has one of the richest and oldest religious histories in the world. The story begins more than 2,000 years ago with Judaism. Ethiopians trace their Hebrew identity back to a legendary union between King Solomon and the queen of Sheba. (Sheba, or Saba, is not a person but a place, a kingdom that probably included Yemen and ancient Ethiopia.) According to the biblical account in the Book of Kings, the queen of Sheba heard stories about King Solomon’s belief in a single god. Leading a fabulous caravan of spices and gold, she went to Jerusalem to meet him. After hearing him talk, she converted to Judaism. That’s where the Bible story ends and Ethiopian tradition begins.

Compared with its Jewish history, Ethiopia’s Christian heritage is relatively new. It dates back only to the fourth century. And Islam arrived in Ethiopia, which was then the Kingdom of Abyssinia, during the seventh century. In A.D. 615, the Prophet Mohammed’s tribe, the Quraysh, attacked him for preaching about one god.

For safekeeping, Mohammed sent his family to the court of an Ethiopian king—a Christian. The descendants of those first Muslims still live in an Ethiopian town called Negash, on land that first king granted them during the seventh century. Tomorrow, I’m hoping to meet them in that northern town of Negash.

Ethiopia is a tricky country. There’s a high level of government repression. I’ve given myself the assignment to write poetry, not political analysis. I’ve also come on a pilgrimage of sorts. After years of writing and thinking about other people’s ideas about God, I want to consider my own for a few days.

At last, the relief of evening arrives. I shower and head up to the lobby, which is full of foreign hacks. Red-faced, many are wearing those ridiculous fisherman-type photographer’s vests. I keep my head down over a fresh lime soda and hope to see no one I know. We all make the same rounds.

Cendón, 36, appears in the lobby wearing a three-quarter-length coat that says Spanish street, not war photographer. That’s one more thing I love about José: He hates cliché. The crows’ feet around his eyes have deepened, but he’s as handsome as ever. We leave for a local Italian restaurant. Italy’s brief colonial legacy is largely culinary. I order the penne arrabiata and he gets the veal piccata. While we wait for our lousy food to arrive, he tells me about the kidnapping, which he has written about. Essentially, their translator sold José and his colleague, British journalist Colin Freeman, to a group of armed bandits who were Somali pirates. Not all pirates live on the sea. This criminal gang marched the men into the mountains all night without water.

Cendón hates thugs. He also hates being told what to do. When Freeman started to stumble, Cendón plunked himself down in the sand and refused to keep walking unless the pirates gave their captives water. By way of an answer, one young kidnapper shoved the muzzle of an AK-47 against Cendón’s forehead.

“You can shoot me if you want. We can’t go on without water,” he told the jumpy gun-boy in the darkness.

“That was pretty brave,” I say.

“We couldn’t keep walking without water.”

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