Not just Romans, many ancient civilisations used water and underground chambers for refrigeration. It's amazing how much we've forgotten with the ease of use of electricity.

Yakhchāl - Wikipedia

Ancient Origins Reconstructing the story of humanity

Ancient Advanced Technology: 2,400-Year-Old Yakhchals Kept Ice in the Desert | Ancient Origins

The yakhchal was a type of ancient ice house (refrigerator) built in the deserts of Persia - demonstrating the human ability to find solutions to p...