Inside Fromme-Birney round barn in Mullinville, Kansas

© Garret Suhrie/Tandem Stills + Motion

Inside Fromme-Birney round barn in Mullinville, Kansas

The round barn design uses gravity and a central silo inside the barn to get hay from the loft to the livestock floor. Despite this work-reducing design, round barns never surpassed the traditional four-sided barn in popularity. Most round barns in the US were built between the mid-19th century until the 1930s, including the Fromme-Birney barn, seen here, built in 1912. Today, the Fromme-Birney Round Barn is on the National Registry of Historic Places.