What is a yakhchāl?

A yakhchāl, meaning 'ice pit' in Persian, is an ancient type of ice house built primarily in the deserts of Persia (now Iran) around 400 BC. These structures served to store ice and food in arid climates, providing crucial cooling during hot summers. A typical yakhchāl features a domed construction above ground and a subterranean storage area. The walls are made from a unique water-resistant mortar called sarooj, which consists of sand, clay, and other materials, providing effective insulation against heat^[1][5][3].

Functionally, yakhchāls utilized an evaporative cooling system in combination with windcatchers to maintain low internal temperatures. This was achieved by accessing water through qanat systems, allowing the freezing of water during cold nights. The yakhchāl could then store this ice for use in hotter months, cooling foods and drinks or even creating traditional Persian desserts^[4][6][2]. Despite the decline in their use with modern refrigeration, many yakhchāls still stand today as a testament to ancient engineering and sustainability^[3][5].