Ice Houses in the Persian Desert

Ancient Persia (Iran) was famous for mud structures to collect fertilizer (pigeon towers) and to create ice in the desert. The ice houses are called yakhchāls.

Beginning around 400 BC, Persian engineers created domed yakhchāls for the production of ice. These can still be seen in Iran in the region of Isfahan. The structures have an underground square-shaped containment area over which the dome was built. The dome and exterior surface of the yakhchal was waterproofed with a layer of mortar called sarooj. It is a mixture of clay, sand, ash, goat hair, and lime.

Ice was brought from the mountains and placed inside the containment area to start the process of freezing. Often walls were built to keep the water shaded as it was channeled to the yakhchāls so it would freeze faster. Water captured in the yakhchal would freeze overnight during the colder months. The ice was then cut into blocks so that it could be transported. In addition to storing drinking water, the yakhchal was also used to keep food from spoiling much as we use refrigerators.

The ice is used to make faloodeh, a traditional Persian frozen dessert made with thin noodles and semi-frozen syrup.

Read more here and here.

Watch this video of the inside of a yakhchal.

Related reading: The Yakhchals of Persia