The nearby Bad Rock Trail was an important route for the aboriginal people who inhabited northwest Montana. The first documented account of the trail was by North West Company trader David Thompson in 1809. Located within sight of the company's trading post, Saleesh House, he reported that it was the scene of many battles between the Kootenai, Salish and the Blackfeet people. Over the ensuing years, the trail became a much cured obstacle on the rod that led up the Clark Fork. It was used by a parade of western notables, including explorers Issac Stevens and John Mullan and by copper-king William A. Clark. Shortly after crossing over Bad Rock in 1841 Father Pierre-Jean DeSmet wrote "I had before seen landscapes of awful grandeur, but this one supposed all others in horror. My courage failed at the first sight."

In 1883, the Northern Pacific Railway blasted away portions of the trail to complete its transcontinental line. The process was repeated in 1936 when the Montana Department of Transportation constructed this segment of the highway. Bad Rock Trail continues to be a commanding presence on Highway 200 in northwest Montana.

Erected by Montana Department of Transportation.