The first practical windmills, featuring sails that rotate in a horizontal plane around a vertical axis, are invented in eastern Persia (what is now Afghanistan), as recorded by the Persian geographer Estakhri in the ninth century.
Made of six to twelve sails covered in reed matting or cloth material, these windmills are used to grind grain or draw up water, and are quite different from the later European vertical windmills.
The authenticity of an earlier anecdote of a windmill involving the second caliph Umar (CE 634–644) is questioned on the grounds that it appears in a tenth-century document.
