The Ancient Persian Ice Pit

A yakhchāl is an ancient ice house found in desert regions. Today it also means refrigerator.

Records show yakhchāls built as far back as 400 BCE to store ice for hot summer days. Ice delivery predates the truck by centuries.

The tall conical shape creates a solar chimney effect. This guides remaining heat upward through openings at the top.

A yakhchāl has a rounded roof above ground level.

Sarooj mortar uses goat hair, sand, clay, egg whites, lime, and ash. It resists heat transfer.

Mughal emperors adopted this technology. Akbar organized ice transport from Kashmir via a 14-stage relay system.

East-west shade walls minimize convection losses, creating up to twenty degrees Celsius cooler than sunlight.

Some pools were 10 m wide. Radiative cooling froze water overnight.