Yakhchal - Persia's Ancient Icemakers

By Heidi Noroozy

Recently, I went shopping for a new refrigerator – a venture that quickly made my head swim. Double doors, top freezer, bottom freezer, pullout drawers, glass or wire shelves, with or without an icemaker that can deliver ice in multiple forms, from crushed to cube, in-door water dispenser, humidity sensors to prolong the life of perishables – refrigerators today can do everything except order groceries. It makes me yearn for simpler times.

Photo by Andreas Praefcke

What I’d really like is a plain old-fashioned icebox, a pretty wooden chest in my kitchen, lead-lined for insulation with a big slab of ice to keep things cold. Well, maybe I could do without lead in close proximity to my food. And I expect the interior might get a bit slushy as the ice melts. Besides, where can you find a reliable iceman these days? But at least I wouldn’t have to battle spoilage when the power goes out.

Or maybe I could just build an ancient Persian yakhchal in my back yard.

Invented around 400 B.C., a yakhchal is a kind of walk-in icebox that looks like a huge, conical beehive. In ancient times, they were built mainly near desert towns to store ice and keep food cold during the scorching summer months.

A yakhchal has two parts: one above ground and the other subterranean. The above-ground dome, which can be as high as 60 feet, is made of a special brick material called sarooj, a mixture of sand, clay, egg whites, lime, goat hair, and ash. The sarooj walls create a waterproof barrier and provide a kind of thermal insulation. Beneath the dome lies the ice pit, a deep cavern dug into the earth for storing ice.

Although “yakhchal” is the modern Farsi word for the contraption we call the fridge (and also a synonym for “glacier”), the ancient versions had a slightly different purpose. Sometimes they indeed stored food, but their main function was to make ice.

Yakhchal near Kerman, Iran

Yakhchals worked like this: a qanat, or underground irrigation trench (sort of like an upside-down aqueduct), transported water to the ice pit, where it would freeze during cold winter nights. The ice was then chopped into blocks and stored in separate chambers, where it could be easily removed as needed.

Some yakhchals operated according to a slightly different principle. Great slabs of ice would be hauled down from the mountains during the cold winter months and stored in the ice pit. As the ice slowly melted, trenches in the floor of the pit collected the runoff, where it refroze during the night and could be cut into blocks for easy transport. Pretty clever, don’t you think?

Most yakhchals had a wall built on the south side to block the searing rays of the sun and shade the ice pit. Tall towers, known as badgirs (wind catchers), were also added for ventilation. By circulating warm air from the surface and cold air from the ice pit, the badgirs acted as a kind of thermostat to better regulate the temperature inside the yakhchal.

I probably won’t build one of these practical ice houses in my small back yard. (Where would I put it?) But I am intrigued by the ingenuity of the ancients, who devised a way to meet the challenges of a harsh climate and enjoy the finer points of life: fresh food and cold drinks on hot summer days.