<p dir="ltr">Refrigerator cars, known as "reefers," keep contents cool with thick insulation. In this photo from a 1930 <em>National Geographic</em>, workers load strawberries onto a refrigerated train in Hammond, Louisiana.</p><p dir="ltr">A century before this picture was taken, most Americans preserved their food with salt or spices, or by smoking or drying it. But during the 19th century, <a href="http://theplate.nationalgeographic.com/2014/07/19/frederic-tudor-king-ice/">"Ice King" Frederic Tudor</a> helped create a new industry by selling and shipping ice to keep food fresh. The icebox became the new necessity, and it stayed that way until electric refrigerators were commercially introduced in the 1910s.</p><p dir="ltr">The pictures in this gallery show refrigerators, not just in stores and homes, but also at roadsides and garbage dumps. Some show old refrigerators that have been repurposed for other uses, like a mailbox or a phone booth. Photo editor Mallory Benedict pulled these shots together because they're "so quirky and unexpected."</p><p dir="ltr">We hope you agree.</p><p dir="ltr">—By Becky Little, photo gallery by Mallory Benedict</p>