The tallest wind catcher (badgir / بادگیر‎ ) standing in Iran (and in the world) is the one in the Dolatabad Garden in Yazd. It’s 34 meters heigh.
Windcatcher (wind tower, wind scoop, badgir / بادگیر‎ ) is a traditional Persian architectural element to create natural air-conditioning system and passive cooling in buildings.
Windcatchers are widely used in Iran, North Africa and in the West Asian countries around the Persian Gulf, and have been for the past three thousand years.

Taller windcatchers catch higher winds. Higher winds blow stronger and cooler (and in a different direction) Higher airs are also usually less dusty.

http://en.wikipedia.org/wiki/Windcatcher

The Dolatabad Garden - Bagh-e Dolat Abad ( باغ دولت آباد), is a beautiful complex which was constructed in 1712 and specially designed for the governor of the time, Mohammad Tagi Khan-e Yazdi to reside with his family.