ELI5: Explain Like I'm 5

Yakhchāl

A yakhchāl is a kind of big pot or oven used in Iran to make ice. Inside the yakhchāl is an underground chamber that stores ice during the summer, and the heat of the sun helps to keep the ice from melting. The yakhchāl also allows for cold air to be released by its cooling system, making it a great way to stay cool during hot days.