Fort Thompson Mounds

The Fort Thompson Mounds are a complex of archaeological sites in Buffalo County, South Dakota, near Fort Thompson and within the Crow Creek Reservation. Declared a National Historic Landmark in 1964, the mound complex extends for a distance of about 6 miles along the Missouri River, and is one of the largest known complex of burial mounds in the Plains region north of Kansas.
The Fort Thompson Mounds are a series of low earthen mounds, extending from the eastern end of the Missouri River's Big Bend, downriver along the eastern bank, past Fort Thompson and the Big Bend Dam. They are generally located on a terrace above the river's bottomlands, roughly 50 feet above the river's typical level in the early 1960s. All of these are believed to be burial mounds, which in some cases overlay older cultural materials.

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