From the record
“Adams Stone Barn is a historic Romanesque Revival barn constructed of stone and wood located about 1 mile (1.6 km) northeast of the town of Sun River, Montana, in the United States. It is the only Romanesque Revival stone barn in the United States located west of the Mississippi River.”
Wikipedia article J. C. Adams Stone Barn, CC BY-SA 4.0.
One of 43 National Register listings published here for Cascade County · listed in 1979 · category: Building.
Sources: the Wikipedia article · the case file at the National Archives · the National Register database, National Park Service