It is a harsh, unforgiving existence for the 1,200 Kyrgyz people who live at the end of the remote and inhospitable Wakhan corridor in Afghanistan, a 140-mile-long strip of land surrounded by China, Tajikistan and Pakistan. Less than half of the children there live to see their fifth birthday. And it is commonplace for women to die during childbirth.

There are no doctors and no roads or vehicles. They live so high up there are no trees. In winter, the temperature goes down to 40 degrees below zero, and there are as many as 340 days of freezing weather a year.

They live in near-complete isolation in a place so removed that the Afghan wars never made it this far.

For thousands of years, the Kyrgyz lived a nomadic life, wandering from Siberia and Mongolia to Kazakhstan and China into Kyrgyzstan and Tajikistan and eventually — about 150 years ago — into the Wakhan.

The grass there was good. The Kyrgyz would spend their summers fattening up their animals and during the harsh winters would move into the lower valleys, which were then in Russia or, on the other side, China.

But the Russian Revolution in 1917 cut off part of that route, and when the Chinese closed their border after the revolution in 1949, some Kyrgyz were trapped in this desolate section of Afghanistan.

Cut off from their brethren on the other side of the borders, they had to adjust to the brutal winters.

Matthieu Paley/National Geographic

Because of the enforced isolation, the Afghan Kyrgyz have been able to hold onto a semi-nomadic life, wintering in mud huts at the plateau and sleeping in yurts in the summer. Occasionally a caravan dips into Pakistan to barter their yaks for wheat flour. They also trade for opium, which has become widely used by the Kyrgyz.

Most of the more than four million Kyrgyz in Tajkistan, Kyrgyzstan and China were moved into collective farms and villages by Communist regimes and lost their nomadic way of life.

Few Westerners have visited the far end of the Wakhan corridor, an area that the Kyrgyz call the “roof of the world.” Among the handful of photographers who have been there, Matthieu Paley probably knows them best. He has made the perilous journey, which can take up to 10 days on foot, eight times. And he has learned the Kyrgyz language.

“The Kyrgyz, they’re tough guys,” he said. “They’re like cowboys without much emotion to show because of the environment. It’s like you’re on the moon more than you’re on the earth, really.”

Photographs from his two latest trips in 2012 are featured in the February issue of National Geographic magazine, accompanied by a story by Michael Finkel.

Matthieu Paley

A book of Mr. Paley’s photographs of the Kyrgyz, “Pamir: Forgotten on the Roof of the World,” was published in October by La Martinière in French and Knesebeck in German. He is trying to get it printed in English, too.

When Mr. Paley, who was born and raised in France, first visited the Wakhan corridor, it was, he said, simply “to see what was on the other side of the mountain.”

“I’m a bit of an explorer,” he added. “I love maps.”

He was living in the far north of Pakistan with his girlfriend, now his wife, Mareile, working with a trekking company and the Aga Khan Foundation. They made their first short trips to the Wakhan corridor by backpacking over a 17,000-foot pass.

In 2005, the couple bought a donkey and walked about 200 miles, over two weeks, alone with no guide or translator, to reach the plateau where the Kyrgyz live. They walked all the way to the Chinese border as Mr. Paley shot photographs.

Mr. Paley became one of the first Westerners to travel the length of the Wakhan corridor in the winter, walking on the frozen Wakhan River to join an anthropologist, Ted Callahan, in 2008 while on assignment for Geo magazine.

Matthieu Paley

Though the land is inhospitable, the Kyrgyz are not poor. Mr. Finkel describes their economy in National Geographic: “Though paper money is almost nonexistent, many camps’ herds contain hundreds of valuable animals, including the horses and donkeys used for transportation. The basic unit of Kyrgyz currency is a sheep. A cellphone costs one sheep. A yak costs about 10 sheep. A high-quality horse is 50. The going rate for a bride is 100.”

They have kept most of their traditional ways, but technology has begun to reach the Afghan Kyrgyz. There are a few solar panels used to charge cellphones. But there is no cell service, so the phones are used as cameras, although there is no way to download the images because there are no computers.

The Kyrgyz have for the most part been forgotten because they inhabit a remote land with few resources. They have been closed off from the world because of political reasons completely beyond their control. They have been able to hold on to their ways, and that inspires Mr. Paley. Despite their circumstances, he said, they seem content.

“There’s horrible things happening, but I’ve been drawn to show the beauty, and the hope and joy,” he said. “When I go there I really enjoy it. There’s laughter, there’s hardship. And this hardship is not depressing; it’s part of life. That’s how it is.”

Matthieu Paley

Follow @paleyphoto, @JamesEstrin and @nytimesphoto on Twitter. Follow Lens on Facebook.