From the record
“The Chicago and Northwestern Railroad Depot in Powder River, Wyoming, also known as Powder River Train Station, was built in 1910. It was listed on the National Register of Historic Places in 1988.”
Wikipedia article Powder River station, CC BY-SA 4.0.
One of 36 National Register listings published here for Natrona County · listed in 1988 · category: Building.
Sources: the Wikipedia article · the case file at the National Archives · the National Register database, National Park Service