John Jacob Astor's American Fur Company built Fort Union Trading Post in 1828 near the junction of the Missouri and Yellowstone rivers in what is now North Dakota (near present day Williston). In its heyday, the post was a busy place and employed up to 100 people. It became the headquarters for trading buffalo hides and other furs with the Assiniboine, Crow, Cree, Ojibway, Blackfeet, and Hidatsa Tribes.

Explore the lives of the Northern Plains Indians on the Upper Missouri. Step into a reconstructed earthlodge and imagine boiling buffalo meat in a clay pot or pounding corn with a mortar and pestle. View the artistry of everyday and ceremonial clothing, bags, and implements. Listen to memories of traditional Hidatsa Indian life, then walk through the past to the Sakakawea site, where earthlodge depressions hint of their life in a vibrant village, alive with games, ceremonies, and trade. The site is located in Stanton.