Below me, Kabul is brown. Everything in Afghanistan is brown. Smog obscures the city, but there's not much to see anyway: mud-brick houses and miles of ruins. Supposedly in the seventies there were paved, tree-lined streets and outdoor cafés and a university and women with faces who wore flowered skirts. Today it is apocalyptic—the destroyed capital of a country that has been at war, with invaders and itself, for 25 years. Make that 25 centuries.

I'm running along thinking about baby-faced, flak-jacketed American soldiers in their armored convoys when I glance at the ground and stop dead in my tracks.

I'm surrounded by rocks painted blood-red. I know what this means—it's the first thing you learn upon arriving in Afghanistan: land mines. My eyes shoot side to side, searching for the rocks painted half red, half white. Cleared paths through minefields are lined with such bicolored rocks, the white side indicating safety.

But there is no path. I hold myself motionless. Try to breathe calmly, look over your shoulder. I am 20 feet into the minefield. Very carefully, step backwards. I place one foot precisely in its own footprint. Do this with the other foot. Delicately, imagining myself as weightless as the ghost I could become, I retrace my steps.

Beside me, the horseman is still smoking. A few days ago, on the road outside Kabul, I met a man whose 11-year-old son, Gulmarjan, was killed by a land mine while tending a flock of goats. Now, in a hazy, smoky dream, I see Gulmarjan running through red rocks, chasing a goat. Suddenly he's up in the air, his face stricken, blood splattering the brown sky and the brown earth and his feet still in his boots but not attached to his knees. My friend Greg's voice floats back to me, saying, "Three million land mines in a country of 25 million—that's at least one for each family... . The Russians made ones that looked like little butterflies. Curious children still pick them up ..."

The horseman is asleep, his face smashed against the wool mat, the pipe still glowing. Gathering up my sleeping bag, I escape the hut. The air is ice-sharp, the sky buckshot with stars, the walls of the encircling mountains black, the snow along their crests as luminescent as a crown. I walk out into the pale-blue steppe and find a spot among the slumbering yaks.

I slide into this distant night in no-man's-land. Lie back, look up, breathe. Safe and sound in this eternally unsafe, unsound country.

IN 2000, GREG MORTENSON and I hatched the idea of traversing the length of the Wakhan Corridor, the thin, vestigial arm of northeastern Afghanistan that extends eastward to the border of China, separating Tajikistan from Pakistan. As founder and director of the Bozeman, Montana–based Central Asia Institute (CAI), a nongovernmental organization that has built more than 50 schools in the tribal borderlands of Pakistan and Afghanistan, Greg had plenty of experience navigating the region's dicey political landscape.