From the record
“The Eckle Round Barn is a historic building that was located near Shelby in rural Pottawattamie County, Iowa, United States. The true round barn was built by Ed Brown and George Robinson in 1928 for Richard Eckle.”
Wikipedia article Eckle Round Barn, CC BY-SA 4.0.
One of 43 National Register listings published here for Pottawattamie County · listed in 1986 · category: Building.
Sources: the Wikipedia article · the case file at the National Archives · the National Register database, National Park Service