The night is cold and silent, with the icy summit of Mt. Kilimanjaro looming against a star-filled sky.
My lungs beg for air as we trudge toward that summit. The loose volcanic rock sends us slipping and sliding. Steam from my breath moistens my face.
"Go slow, go slow," cautions mountain guide Godwin Roland. "It gets harder."
It had looked so easy from afar, with Kilimanjaro rising gently from the green and gold African savanna into a halo of swirling clouds.
Africa's tallest mountain lures visitors with its majesty and its mystery, immortalized in both local African legends and Western tales such as Ernest Hemingway's "The Snows of Kilimanjaro."
"Everyone wants to climb the mountain because it is so beautiful," Roland told me before we started. "But," he warned, "it is never easy."
More than 10,000 people--mostly Americans and Europeans--try each year, though fewer than half reach Uhuru (Freedom) Peak at 19,342 feet. There are now marked trails and solar-powered A-frame huts for a good night's rest at the lower altitudes.
Roland, who never tires, has been a constant source of encouragement since our departure from the weather-beaten Kibo Hotel at the base of Kilimanjaro.
Roland's ancestors prayed toward the mountain they considered God's throne. They never dreamed of climbing it before the arrival of Westerners, who came with the impulse to conquer rather than worship. There is no record of an African scaling Kilimanjaro before a German, Hans Meyer, reached the summit in 1889.
With its relatively mild slopes--the mountain is 50 miles by 30 miles--Kilimanjaro can be scaled without mountain-climbing expertise. But reaching the summit is as demanding as a marathon run.
I carry all my own supplies except food. I am given two porters, one of whom must carry on his head a crate of food for all of us. It weighs 90 pounds, almost as much as he does.
On our four-day trek to the top, we pass through a different world each day, beginning on a steamy, equatorial morning.
The rain forest is so tangled that spider webs stretch from one moss-covered tree trunk to the next. The howls of colobus monkeys echo through the trees, but the creatures are invisible in the thick brush that forms an arch over the trail. The din of insects sounds like a choir humming.
Elephants, lions, leopards, rhinos and other great beasts that used to inhabit this realm have vanished due to poaching and the influx of humans.
"Close to the western summit there is the dried and frozen carcass of a leopard. No one has explained what the leopard was seeking at that altitude," Hemingway wrote.
The leopard's remains, discovered in 1926, vanished in the 1960s in the hands of mountain climbers, who are now the most prominent species on Kilimanjaro.
At our first rest camp there are more than 20 climbers, most in bright nylon.
The altitude is supposed to suppress one's appetite, but my porter, Foster Chao, fixes me a dinner of soup, bread, chicken, potatoes, carrots and tea that would feed four. He offers more, partly out of generosity, partly to lighten his own load.
My belly is full as we leave the forest for the rolling grasslands watched over by crowned hawk eagles gliding in slow, lazy circles, searching for the mice that skitter across our trail.
But as we near 15,000 feet on the third day, the mountain turns moody, wrapping itself in cold, swirling clouds that bring sleet and snow to the black moonscape.
On the final night, a wood stove in a cinder-block barracks dries my socks and warms the tea before we make our nighttime assault on the summit.
Roland and I begin our ascent just after midnight, when the black rock and gravel is frozen, and hence a bit more stable. Roland's lamp is out of kerosene, but I follow his footsteps up a rocky slope so steep we must travel in a zigzag path the entire way.
I chant Roland's "go slow" advice like a mantra, but still stop every 10 minutes in a futile attempt to catch my breath while bent over my walking stick. Roland, a veteran of 40 climbs, puffs a cigarette.
The thin air makes my head throb. My chest tightens. My words form a drunken slur. My blistered toes bleed, but my feet are too numb for me to notice. My legs rebel against their marching orders.
After four hours, as the blackness starts to fade from the sky, we reach the rim of the volcano, the summit in sight.
Awed by the beauty, I throw up my breakfast in one violent heave that comes without warning, as if caused by a punch to the stomach. I wash my mouth with a handful of snow. To my surprise, I feel much better--my headache gone, my breathing less labored.
From memory, Roland follows a hidden trail through fresh, knee-deep snow for an hour until we can't go any higher.
His timing is perfect. We reach Uhuru Peak as the morning sun sends streaks of pink and orange across the East African sky.
The only sound is of boots crunching fresh snow. The clouds below merge seamlessly with snowbanks on the mountainside. The only competing mountain is Mt. Meru, 14,000 feet high and 40 miles to the west, a mere foothill from our vantage point.
Roland and I sit next to a rusting iron cross that marks the summit. We watch the sun rise until the glare from the ice stings our eyes.
I take a few pictures. Then there's nowhere to go but down.