Yakhchal in Yazd Province

By 400 BC, Persian engineers had mastered the technique of storing ice in the middle of summer in the desert. The ice was brought in during the winters from nearby mountains in bulk amounts, and stored in a Yakhchal, or ice-pit.

Above ground, the structure is comprised of a large mud brick dome, often rising as tall as 60 feet tall. Below are large underground spaces, up to 5000m³, with a deep storage space. The space often had access to a Qanat, or wind catch and often contained a system of wind catchers that could easily bring temperatures inside the space down to frigid levels in summer days.

Pretty smart.

For more see:  http://www.eartharchitecture.org/index.php?/archives/1045-Yakhchal-Ancient-Refrigerators.html