The ancient vertical-axis windmills of Nashtifan, Iran, stand as marvels of engineering and a testament to human ingenuity.
Situated in the northeastern province of Khorasan Razavi, Nashtifan is renowned as one of the windiest locales in Iran, experiencing wind speeds that frequently exceed 120 km/h (75 mph). Approximately 30 windmills, commonly referred to as “wind catchers,” were constructed here a millennium ago to harness the formidable wind energy, primarily for grinding grains into flour to make bread.
On the southern outskirts of the town—whose name originates from terms meaning “storm’s sting”—a massive earthen wall towers to a height of 65 feet (20 meters), offering protection to the residents against the harsh gusts of wind. This imposing wall serves as a backdrop for the ancient windmills, the majority of which remain operational and have been in use since the ancient Persian era.
The design of the windmills – the first known documented arrangement of this kind – is unique in featuring a vertical-axis rotor directly connected to the grinding stone. This distinguishes it from the more common horizontal-axis windmills found in Europe and other parts of the world.
The vertical-axis design offers several advantages over the horizontal-axis design, particularly its capability to operate effectively in high winds. However, one drawback of this setup is that, due to their horizontal rotation, only one side of the wind blades can capture wind energy, while the other side must work against the wind direction, resulting in energy loss. Despite this limitation, the vast wind energy available in the region compensates for the disadvantage.
The windmills of Nashtifan are constructed entirely from clay, straw, and wood. Each windmill’s rotor is composed of six wooden blades, approximately 5 meters (16 feet) in height and 50 centimeters (20 inches) in width. These blades are attached to a vertical shaft that extends down to a room made of clay, housing the grinding stones.
As the rotors rotate, they generate vibrations that induce the movement of grains from their container to the grinders, facilitating the production of flour.
When the wind is blowing, this simple yet effective system is capable of producing flour bags weighing up to approximately 330 pounds (150 kilograms). Positioned above the grinding stones is a tank where grains are placed. The amount of wheat flowing from the tank to the stone hole is controlled by the pressure and speed of the wind, eliminating the need for an operator to oversee the entire grinding process.
Unsurprisingly, the windmills of Nashtifan have been a crucial component of the local economy for centuries. Apart from grinding wheat, they have provided employment opportunities for local craftsmen and millers.
Today, the windmills continue to be utilized by the local community, although they have largely been supplanted by modern mills powered by electricity. Nevertheless, they remain an important part of the cultural heritage of the region and are a popular tourist attraction.
In 2002, the windmills of Nashtifan were officially recognized as a national heritage site by the Iranian Cultural Heritage Organization. Despite this designation, the windmills face several challenges, including the impacts of climate change, leading to a decline in wind speeds in the region. Additionally, the windmills require conservation and restoration efforts to ensure their continued operation for generations to come.
Currently, the ancient mills are maintained by Ali Muhammad Etebari, a friendly custodian who does not receive any compensation for his unofficial village role. He stated to a film crew from the International Wood Culture Society with a hearty laugh and a playful gesture, “If I don’t look after them, the youngsters will come and spoil it and break everything.”