From the record
“The Cottonwood Creek Bridge is a bridge in Fallon County, Montana near the town of Ismay, built in 1934. It was listed on the National Register of Historic Places in 2014.”
Wikipedia article Cottonwood Creek Bridge (Ismay, Montana), CC BY-SA 4.0.
One of 3 National Register listings published here for Fallon County · listed in 2014 · category: Structure.
Sources: the Wikipedia article · the National Register database, National Park Service · the Wikipedia article