Eli5: How did people make and keep ice in medieval times, and how do we manufacture ice cubes now ?

Question

Eli5: How did people make and keep ice in medieval times, and how do we manufacture ice cubes now ?

In: Technology

Answer 1

The opening scene of Frozen shows the process of harvesting ice which has been little changed since medieval times. Blocks would be cut and then transported to cities. In the 1850’s ice was harvested in Alaska, where they build sawmills for the purpose of making sawdust to insulate the ice for shipping to California.

However, going back to the medieval period, once the ice was harvested, it would be placed in stone and earth ice houses. [This giant ice house](https://en.wikipedia.org/wiki/Tugnet_Ice_House) is just down the road from me and was used for preserving salmon. Castles would have their own, smaller ice houses.