Ancient refrigeration: Depending on the climate, ancient civilizations preserved food using natural cooling methods available to them. People took advantage of rivers and lakes by storing food directly in the cold water or cutting ice for ice houses. Storage pits in the ground were filled with snow or ice and often covered with insulating materials like straw or sawdust.
Refrigeration without electricity: Ice houses on lakes and rivers were still effective ways to keep food cool before the invention of electricity. If ice or snow wasn’t an option, underwater or underground storage, like cold cellars, provided refrigeration. People also began building their own iceboxes for cold storage, using chunks of ice or snow in boxes insulated with natural materials like sawdust or seaweed.
Manufactured iceboxes that looked closer to modern refrigerators became popular in the 1800s. These designs consisted of insulated metal or wooden cabinet-type structures with a tray or compartment that held a large block of ice. These ice blocks were regularly delivered to households with iceboxes.