From the record
“August Nus Polygonal Barn is a historic building located east of Arlington, Iowa, United States. Built in 1906, this was one of four flat roofed barns that were known to exist in Iowa, and it was the oldest of the four.”
Wikipedia article August Nus Polygonal Barn, CC BY-SA 4.0.
One of 29 National Register listings published here for Fayette County · listed in 1986 · category: Building.
Sources: the Wikipedia article · the case file at the National Archives · the National Register database, National Park Service