Frostkeeping

In the mountains of Isturoth, there is no shortage of ice and snow. In the high-altitude regions of the Coldlands, Frostlands and Icelands, preserving food and supplies is much easier, as the weather is frequently cold and ice is readily available.
Lower down the slopes, however, in the green valleys of the Highlands and Lowlands, this is much harder to accomplish. This is how the practice of "frostkeeping" has been developed over time. 

Ice-Pits

For use by the wider town or settlement, the ice needed for food preservation is brought in during the winters from nearby mountains in bulk amounts, and stored in an ice-pit.
These structures have been used primarily to store ice for use in the summer, as well as for food storage. The ice is also used to chill treats for royalty during hot summer days and to make clean drinking water when there are no freshwater sources nearby.
Aboveground, the structure is comprised of a large stone or clay dome, often rising as much as 60 feet tall. Below are large underground spaces with a deep storage space. The space often has access to windcatchers that can easily bring temperatures inside the space down to frigid levels in summer days. These ice-pits often come with channels at the bottom to catch what water comes off the melted ice and brings it outside, allowing it to re-freeze during the night times or merely as a run-off for agriculture or drinking water for animals.

Ice Boxes

The ice stored in the local ice-pit can be brought to an individual's personal storage, their own cabinet or chest where they keep their food and any other perishable goods. Normally, with the inside temperatures being warmed to comfortable levels, this ice will melt relatively quickly and need to be replenished often.

Access & Availability

While initially popular only in larger cities, the technology has been brought to smaller and more obscure towns throughout Isturoth.