C.A. Rownd Round Barn - Credit: Wikimedia Commons
The C.A. Rownd Round Barn is a historic building located in Cedar Falls, Iowa, United States. It was built in 1911 by C.A. Rownd. It is constructed of ashlar-faced blocks that Rownd manufactured on the site. The barn was featured in the April 1912 edition of The Farm Cement News, which was published by Universal Portland Cement. with a The building is a true round barn that measures in diameter. It has been listed on the National Register of Historic Places since 1986. Read more on Wikipedia
Source: en.wikipedia.org