How did they keep things cold back in the old days?

Answer 1

1) A cool place: usually a well-ventilated pantry on the north side of the house, supplied with marble slabs for shelves. Marble doesn't actually keep things cool, but it is cold to the touch. Cellars were also used - more effective because never exposed to sunlight, even through a wall; but subject to the growth of mould. 2) Evaporation. Items needing coolness could be covered with a damp cloth, or with a well-soaked porous pot. This method of cooling actually does work. Cellars, again, were usually damp and therefore also cooled by evaporation. 3) In a running stream, preferably one coming off a high mountain, which would run cold all summer. 4) For the rich, ice houses. Usually dug into the side of a hill, these were insulated by a depth of earth. Ice from ponds could be piled up in winter, and a sufficient quantity could last through most of the summer with careful management.

Answer 2

In the past, people used ice houses or root cellars to keep things cold. Ice would be harvested from frozen rivers or lakes in the winter and stored insulated with straw or sawdust to last throughout the year. Root cellars were dug underground to utilize the cooler temperatures for preserving food.