The Windmills of Nashtifan: Iran's Thousand-Year Machines That Still Turn
On a windswept ridge above the small town of Nashtifan, in Iran's Razavi Khorasan province close to the Afghan border, stands a long row of earthen towers that have been catching the wind for centuries. These are asbads: vertical-axis windmills built of clay, straw and wood, working on a design that written sources trace back more than a thousand years in this corner of the world. When the fierce seasonal wind arrives each summer, their wooden blades still creak into motion, and millstones that belong to a pre-industrial world still grind wheat into flour. Few working machines anywhere on Earth carry so much history in their timbers, and almost none do so while still performing the job they were built for.
The wind of one hundred and twenty days
The engine behind everything at Nashtifan is a wind so reliable that it has its own name. Iranians call it the bad-e sad-o-bist-roz, the wind of one hundred and twenty days. From late spring until early autumn, air pours down from the highlands of Central Asia, is squeezed between the mountain ranges along the border of Iran and Afghanistan, and races across the plains of eastern Khorasan and Sistan. It is one of the most persistent seasonal winds on the planet: not an occasional gale but a near-constant presence for roughly a third of the year, strong enough to strip topsoil, sandblast walls and make summer life genuinely exhausting. Most communities would treat such a wind purely as a hazard. The people of this region did something far cleverer. Instead of merely enduring the wind, they built machines to harvest it, and they placed those machines exactly where it blows hardest, on the exposed ridge above their houses. Local tradition even explains the town's name as a reference to the sting of the storm, a hint that the wind shaped the community's very identity. Here, when the milling season and the wind season coincide, geography stops being a curse and becomes an engine.
Spinning on a vertical axis
Nearly every windmill in the European imagination, from the Dutch polder mill to the tower mills that Don Quixote charged at, spins on a horizontal axis, with sails facing the wind like an aircraft propeller. The asbads of Nashtifan work the other way around. Their rotors turn about a vertical shaft, like a carousel or a revolving door, a configuration engineers call a panemone. Each mill is arranged on two levels. In the upper chamber, tall wooden blades are mounted on a massive timber shaft. In the lower chamber, that same shaft drives the millstone directly. Because rotor and stone share a single upright axis, no gearing is needed to redirect the motion, a crucial simplification in a world without cast iron. The real trick lies in the masonry. A high wall shields one half of the rotor, while openings funnel the incoming wind onto the other half. With one side pushed and the other side sheltered, the rotor spins steadily in a single direction for as long as the wind holds. Drag-based vertical rotors extract less energy from a given breeze than modern lift-based blades, but where the wind blows for a hundred and twenty days almost without pause, efficiency matters far less than simplicity, robustness and the ability to run unattended.
A millennium of written records
How old are these machines? The honest answer comes in two parts. The individual structures standing at Nashtifan today have been repaired, replastered and partially rebuilt over many generations, because mud-brick architecture demands constant maintenance; pinning a precise construction year on any single wall would be misleading. The design, however, is unambiguously ancient. Medieval geographers and historians writing in Arabic and Persian described windmills in the Sistan region of eastern Persia as early as the ninth and tenth centuries, noting with admiration how its people used the wind to grind grain and raise water. Those accounts are among the earliest reliable descriptions of windmills anywhere, which is why historians of technology so often point to this corner of the Iranian plateau as a birthplace of wind power. How the idea travelled afterwards remains debated: it may have moved westwards along trade routes and eventually inspired Europe's very different horizontal mills, or Europe may have arrived at the windmill independently. What is certain is that when the first well-documented European windmills appear in the twelfth century, the wind machines of eastern Persia already had centuries of working history behind them.
Architecture of earth, straw and wood
The materials of the asbads could hardly be more local. Their walls are raised from sun-dried mud brick and coated with kahgel, the traditional Persian plaster of clay mixed with chopped straw that gives so many buildings in Khorasan their warm ochre skin. Timber, always precious in this arid landscape, is reserved for the parts that move: the great vertical shaft, the radial arms, and the blades, which are assembled from wooden slats and bundled reeds rather than from cloth sails. Seen from the town below, the mills read less like separate buildings than like a single fortified wall crowning the ridge, its tall openings turned toward the incoming wind. That is no accident. The row of mills doubles as a windbreak, absorbing the first blast of the seasonal storms and sheltering the houses, courtyards and gardens behind it. Even the siting is a piece of quiet engineering: along the ridge line the wind arrives compressed and accelerated, so the mills stand precisely where the resource is richest. This is vernacular architecture in the fullest sense, built from the ground it stands on, shaped by the wind it feeds on, and serving the town twice over, as mill and as shield.
Grinding grain in the wind season
Operating an asbad was skilled, seasonal work, and the calendar was generous: the wind season arrives just as the wheat harvest comes in. Farmers carried their grain up to the ridge, and the miller took over from there. He controlled the flow of wheat from the hopper into the eye of the stone, judged the fineness of the flour by rubbing it between his fingers, and could tell from the pitch of the creaking timbers whether the rotor was running too fast for safety. There were no brakes in the modern sense; managing an asbad in a hard blow meant working with the openings and the grain flow rather than fighting the wind directly. The flour that came off the stones fed the bread ovens of the town through the rest of the year. In recent decades, that body of knowledge has narrowed to a handful of elderly custodians. Travellers and documentary makers who visited Nashtifan in the 2010s found the site kept alive largely by one aging guardian who greased the shafts, patched the plaster and set the stones turning for visitors. His worry, often repeated, was that the young see no future in mud and wind. That quiet anxiety is the real story behind the picturesque photographs.
Heritage recognition and an uncertain future
Iran formally recognised what it has at Nashtifan by registering the windmills as a national heritage site in 2002, and the asbads of the wider region have since been put forward on UNESCO's tentative list of World Heritage candidates. Recognition on paper, though, does not by itself keep mud brick standing. Wind-blown sand abrades the plaster, rare but violent rains gnaw at the walls, and timber shafts crack if they are not regularly maintained by hands that know the work. Restoration campaigns can rebuild walls, but the deeper challenge is keeping the craft itself alive: an asbad without a miller is a monument, not a machine. Meanwhile, the underlying idea has acquired an unexpected second life. Modern engineers developing vertical-axis wind turbines for rooftops and city streets are working, knowingly or not, in the tradition that the millwrights of Khorasan pioneered: rotors on upright shafts that trade peak efficiency for simplicity, quiet running and tolerance of harsh conditions. A field test lasting many centuries on a ridge in eastern Iran suggests that this trade-off can be well worth making.
Explore on the map
Nashtifan lies in Khaf County in Iran's Razavi Khorasan province, and you will find it marked, together with thousands of other historic and working windmills around the world, on our interactive map. Zoom in on eastern Iran to see the asbads in their landscape, then drift westwards and compare them with the horizontal-axis mills of the Netherlands, Spain or England. Few journeys across the map cover more centuries of wind power in a single glance.