The submission consists of 18 Illinois round barns located throughout the state.

In 1983, 1992 and 2003 one property was added to the submission and in 1994 a historic district at the University of Illinois, including three round barns, was added to the submission and the National Register of Historic Places.

The highest concentration of round barns on the submission occurs in Stephenson County.

Five Stephenson County round barns were added to the National Register on February 23, 1984.

[2] Seven round barns were added to the National Register per the original MPS in 1982.

[2] On the original January 1984 nomination seven round barns were included in the Stephenson County area, of those six were added to the MPS and, thus, the National Register of Historic Places.

[2] The Robert Weber Round Barn is in nearby Winnebago County.

The Buckles Round Barn, located in Logan County near Mount Pulaski, was added to the National Register of Historic Places, and the Round Barn MPS, on February 10, 1983.