Nahbandan windmills,

Nahbandan windmills, also known as Khwansharf windmills, are a collection of windmills located in Khwansharf village near Nehbandan city in South Khorasan province. These mills date back to the Qajar period and were used to grind wheat and barley.
Nahbandan windmills are tower mills and use wind power to rotate blades and millstones. These mills have two floors. The lower floor is where the millstones are located and the upper floor is where the vanes and other mill equipment are located.
Nehbandan windmills are among the tourist attractions of South Khorasan province due to the use of renewable wind energy as well as their traditional architecture.
Here are some interesting features of Nehbandan windmills:
Use of wind power: These mills use wind power to rotate blades and millstones.
Horizontal axis: Unlike European mills that have a vertical axis, these mills use a horizontal axis.
Two floors: these mills have two floors. The lower floor (the barn) is where the millstones are placed, and the upper floor, which is exposed to the wind, is the working space for the main parts of the mill.
High walls: On the upper floor, there are two parallel walls with a height of approximately 10 meters, which create a channel for the passage of wind.
Big vane: Between these two walls, there is a big wooden vane that rotates with the wind.
Millstones: On the lower floor, there are two large millstones of the same size, which is the fixed lower stone and the movable upper stone.
Flour and wheat storage warehouse: On the ground floor, there are warehouses for storing flour and wheat.
National registration: Due to their historical and architectural value, these mills were registered as one of the national works of Iran in 1379.

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