Yakhchal is a building allows cold air to pour in from entries at the base of the structure and descend to the lowest part of the Yakhchal, large underground spaces up to 5.000 m3 (180,000 cu ft) in volume. At the same time, the tall conical shape of the building guides any remaining heat upward and outside through openings at the very top of the building,and through this active process the air inside the yakhchal remains cooler than the outside.
