All was going according to plan. It would probably take them four hours to clear it. We would not have to rope down from a hover after all; the chopper would be able to land firmly on the ground.

Chris Fisher, Dave Yoder, and Lucian Read went in the next flight. Two hours later, the chopper returned and refueled, and then Juan Carlos and I walked out onto the hot tarmac to get in. We each had backpacks with all our essential gear, including food and water for two days, as the camp would not be fully stocked for at least forty-eight hours. We would have to be self-sufficient for those first few days. Because the LZ at the site was so small, and the AStar unable to carry more than a tiny amount of equipment, most of it would be ferried into the valley on the Bell, offloaded at the downstream LZ, and from there shuttled in by the AStar in many back-and-forth trips.

Juan Carlos and I stowed our two backpacks in a basket attached to the port side of the helicopter, since there wasn’t room inside. Steve Elkins brought out his iPhone, and he taped me as I gave a ten-second video farewell to my wife, Christine, since I would be out of contact for the next nine or ten days. It was strange to think about what might happen before I was next in touch with her. Steve promised to e-mail the video to her when he got back to Catacamas.

Just before we lifted off, I had a chance to chat with our copilot, Rolando Zuniga Bode, a lieutenant in the Honduran Air Force. “My grandmother used to talk about Ciudad Blanca all the time,” he said. “She had a lot of stories.”

“What stories?”

Rolando dismissed them with a wave of his hand. “You know, the usual old superstitions. She said the conquistadors found the White City and went in there. But they made a mistake: They picked the flowers—and they all died.” He laughed and wagged his finger. “Don’t pick the flowers!”

Juan Carlos and I donned our helmets and buckled in. He was excited. “When I first saw the images with the buildings, the dimensions of those things—they are big—I had ten thousand questions. Now we’re about to find the answers.”

After the helicopter took off, we fell silent, taking pictures of the amazingly green and rugged landscape unfurling below.

“There’s Las Crucitas,” Juan Carlos said. “I asked the pilot to take us this way.”

I looked down at the remote archaeological site, the largest that had ever been found in Mosquitia before the identification of T1 and T3. In an open, grassy area, I could see a series of sharp mounds, earthworks, and plazas, situated on both sides of the Río Aner. Many had speculated that this was Morde’s Lost City of the Monkey God, but of course now we know Morde had found no such thing—and had never even entered this region of Mosquitia.

“It looks a lot like T1, don’t you think?” Juan Carlos said.

I agreed. From the air it looked strikingly similar to the lidar images—the same bus-like mounds, same plazas, same parallel embankments.

Beyond Las Crucitas the serious mountains loomed up, some almost a mile high. As we maneuvered our way through them, the clear-cuts gave way to unbroken cover. At one point, with Rolando at the helm, the chopper swerved violently.

“Sorry. I dodged a vulture,” he said.

Finally the telltale notch into T1 loomed up ahead, and in a moment we had cleared it and were inside the valley. Two scarlet macaws glided below us as we followed the line of the river. Pressed to the window, I took pictures with my Nikon. In a few minutes the landing zone came into view, a green patch littered with cut vegetation; the chopper turned, slowed, and descended. Woody knelt at the edge of the LZ, signaling the pilot as he came down. The trees and bushes around us thrashed with prop wash as we descended, the river surface whipped into a froth of white water.

And then we were on the ground. We’d been ordered to grab our gear and get clear of the LZ as fast as possible, keeping our heads down. We jumped out and seized our stuff, while Woody and Sully ran to the chopper and unloaded gear and supplies from the basket, throwing them into a pile at the edge of the LZ; in three minutes the chopper was back in the air.

I watched it rise above the trees, pivot, and disappear. Silence descended, soon filled by a strange, loud roaring from the forest. It sounded like some giant machine or dynamo had been started and was cranking up to full speed.

“Howler monkeys,” said Woody. “They begin calling every time the helicopter comes in and out. They seem to respond to the noise.” The landing zone had been macheted from a thick stand of “lobster claw” heliconia plants, also known as false bird of paradise, their fleshy stumps oozing white sap. The red-and-yellow flowers and dark green leaves were strewn everywhere, carpeting much of the LZ. We hadn’t just picked the flowers; we’d massacred them. A part of me hoped that Rolando hadn’t seen this as we landed.

Woody turned to us. “Grab your kit, get a machete, pick out a campsite, and get yourself fixed up.” He nodded toward the impenetrable wall of jungle. A small dark hole, like a cave, had been cut into it, offering a path in. I hoisted my pack; Juan Carlos did the same; and I followed him into the green cave. Three logs had been laid across a pool of mud, and beyond that the freshly cut trail went up a five-foot embankment. We came out in a deep, gloomy forest, with trees rising like giant cathedral columns into the unseen canopy. Their trunks, ten to fifteen feet in diameter, were braced with massive buttresses and knees. Many were wreathed in strangler figs, called matapalos (“tree killers”). The howler monkeys continued roaring as my eyes adjusted to the dimness. The air carried a thick, heady scent of earth, flowers, spice, and rotten decay. Here, among the big trees, the understory was relatively open and the ground was flat.