Fort Thompson Mounds

Fort Thompson Mounds is a series of burial mounds spread across several miles along the Missouri River on raised terraces above the floodplain. The structures vary in size and height, creating a distinctive pattern of earthworks that spans the landscape.

These mounds were built over a very long period, with some of the oldest dating back thousands of years and others added in more recent periods. The continuous use of this location shows how important the Missouri River site remained for multiple cultures across time.

These mounds served as burial grounds where communities gathered to honor their deceased over many generations. The layout and spacing reveal how people organized themselves socially and maintained connections across different family groups and settlements.

Access to this protected archaeological site is limited and visitors must follow guidelines to avoid damaging the mounds and surrounding landscape. Wear sturdy shoes and stay on designated paths to help preserve these structures and protect the delicate ground surfaces.

Researchers found that people used this area across several thousand years, with different cultures settling here one after another and leaving their marks. This long continual presence makes it one of the rarest examples of sustained human habitation along the Missouri River.

Location: South Dakota

GPS coordinates: 44.03063,-99.37657

Latest update: December 14, 2025 17:03