In celebration of the ten-year anniversary of Paul Salopek's first steps on his Out of Eden Walk journey, this dispatch is now available for educational use in fifth- and eighth-grade reading levels. The original text is available as the default reading level, as well as on the Out of Eden Walk website.

By Paul Salopek

PIGISH, AFGHANISTAN (10/23/2013)

In remotest Afghanistan, a 2,000-year-old technology still churns out flour—and life.

The hut is tiny, windowless, and made of round river stones. It stands alone in a high, wild valley in Afghanistan.

From about 60 feet away you can hear it hum. A strange sound like a long sigh comes from its walls. The soft, dry, song-like noise rarely stops. Every once in a while, a man and a boy step out of the doorway into sunlight. They are covered in white dust from head to toe. They look like pale beings from another world. They wipe their faces with a rag. They go back inside.

Is this some sort of sacred site? Is the rock hut a shrine to a forgotten cult? Are the man and boy ghosts?

The answer to all these questions is: yes.

Inside the small building a 600-pound granite wheel turns on a spindle. The spindle is attached to wooden vanes. The rush of ice water inside a canal moves the vanes in circles. The water comes from a faraway glacier on the Afghanistan-Pakistan border. The water’s power turns seeds of wheat into clouds of flour. Flour is an important part of life for the local farmers. Their main meals are bread and tea. The man and boy work well together. They are father and son. It’s clear they love each other very much. The father cleans the boy’s powdered face. The small boy watches his father carefully, eager to follow his commands. They both belong to what is possibly the last generation of waterwheel millers in the world.

Humans have been using the power of water to crush grain since at least the first century B.C.

Around that time, a historian included a flour mill on a list of things acquired through Rome’s conquest of southern Turkey. Earlier, another writer wrote a poem celebrating the freedom water mills gave Greek women. These women once spent their lives bent over stones, or querns, grinding their crops.

Women who toil at the querns, cease now your grinding;
Sleep late though the crowing of cocks announces the dawn.
Your task is now for the (water) nymphs . . .

Water mills were the first robots of ancient times.

They were common in the farming world from China to Arabia to Europe. Their presence everywhere proves how effective they were. Records from the Middle Ages show around 6,000 gristmills were in England alone by 1085 A.D. That was about one mill for every 40 households.

By 1900, fossil fuels sent most water mills into history, except in the Wakhan Corridor of Afghanistan.

The region is surrounded by 20,000-foot mountains and has tumbling glacial creeks. The people of this remote part of Badakhshan Province depend on the power of running water to eat and survive.

In the tiny village of Pigish, where many peaceful Shia Ismaili farmers live, five busy water mills are used through the autumn harvest season. Just as in medieval Europe, each mill is family owned and taxed by the government. Milling is an honorable profession, passed down through families for decades or even centuries. The farmers push their sacks of wheat to the mills in wheelbarrows. These barrows are often made of rough planks. The people here also build their own mud-brick houses, saw their own poplar roof beams, and sew their own burlap donkey saddles. They also braid their own yak hair ropes, carve their own wooden shovels, and build their own stone aqueducts. Aqueducts are systems of human-made canals that carry water from place to place. It’s a pleasure to walk through the Wakhan Corridor.

Sultan, who is 38 years old, works in the small stone water mill with his nine-year-old son, Shambe.

Finally, I see them on a break. They sit on a blanket outside the mill. They don’t speak. The mill speaks. Together, they stare up the sunlit valley, almost shyly. They sip from cups of tea they pour for each other from a dented iron kettle.

View the original dispatch to see a video of Sultan at work in the mill.