Vertical-Axis Desert Windmills

Vertical-Axis Desert Windmills is an original illustration set in Nashtifan, Razavi Khorasan, Iran. It lies in the subtropics, where the climate is cold desert — arid, with freezing winters.

A long mud-brick ridge building presents a row of tall vertical slots, each exposing a wooden vertical-axis sail assembly turning in the same strong wind. Grain sacks and a millstone room sit on the sheltered side; dust streams across a sparse plateau beneath a hard blue sky.

Why are wooden sails hidden inside a long wall of narrow slots?

The wall concentrates the prevailing seasonal wind through each slot while sheltering the machinery from cross-gusts. Vertical shafts carry rotation directly down to millstones, avoiding the heavy gearing needed by a horizontal-axis mill, and lining many units along one exposed ridge harvests the same reliable airflow. Dust, mud brick, direct-drive sails, and ridge orientation make this a landscape built around eastern Iran's powerful winds.

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