by Saghar Nazari 

Ice houses buildings used to restore ice throughout the year before invention of refrigerator. As architecture of Iran was a response to the needs of human life and temperature factors, these dome shaped structures designed to protect ice from melting in hot summers of Iran

specially in cities and villages located near the desert.
A cuneiform tablet from 1780 shows the construction of an icehouse in northern part of Mesopotamia, also in 7th century BC there are remains of ice pits in China. In Rome in 3rd century AD also ice was imported from mountains and then stored.By 400 BC Persian started to use some techniques of restoring ice in Yakhchals to be used in summer.
Yakhchāl (yakh means "ice" and chāl means "pit") is an ancient type of evaporative cooler. it has a domed shape structure and also it has subterranean storage space; it was used to store ice and sometimes food as well. The subterranean space coupled with the thick heat-resistant construction material insulated the storage space year round. These structures were mainly built and used in Persia. Many that were built hundreds of years ago remain standing.
The water is channeled from Qanats or nearby mountains to the ice house. Behind each icehouse there are long water channels which are protected from the heat during the day with some shade walls.

Over the surface of this channels a thick layer of ice is formed overnight and it will be collected before sunrise and packed with straw or straw dust and moved to ice house. This would be repeated for some days until having enough ice. In some yakhchāls, ice is also brought in from nearby mountains for storage or to seed the icing process.
This structure is built of unique water resistant mortar called sarooj which is composed of sand, clay, egg white, goat hair and ash. This material acts as an insulation. The sarooj walls are at least two meters thick at the base.
More commonly, yakhchāls equipped with a system of bâdgirs (ancient design of wind catchers or wind towers) that could easily bring temperatures inside the space down to frigid levels even in summer days.

Icehouse in addition to the usage of storing ice also is used to store food and dairy.