Fort Mandan (Washburn, North Dakota)

Washburn · North Dakota

Quick BriefFort Mandan was the winter encampment built by the Lewis and Clark Expedition in 1804–1805 on the Missouri River approximately twelve miles from present-day Washburn, North Dakota. Construction began on November 2, 1804, and the fort was completed on December 24, with the American flag raised on Christmas Day—the first time the nation's flag was displayed over what is now North Dakota.
Open to visitors
Fort Mandan, North Dakota

History & Significance

The expedition chose this location near the Mandan and Hidatsa villages after finding these peoples friendly and helpful. The triangular fort was constructed from cottonwood timber cut from the riverbanks, with an 18-foot-high stockade surrounding the perimeter.

The winter proved brutally cold, with temperatures sometimes dropping to −45 °F, and several expedition members suffered frostbite. Lewis and Clark compiled extensive descriptions of the Missouri tributaries, Native nations encountered, and specimens collected—material later sent to government officials in St. Louis as the Mandan Miscellany.

The fort was also where Lewis and Clark appear to have first met Sacagawea, the Shoshone woman whose Hidatsa-speaking husband Toussaint Charbonneau served as an interpreter; their son Jean Baptiste was born on February 11, 1805, possibly at the fort. When the expedition returned in August 1806, a fire had destroyed the original fort, and the Missouri River eventually eroded the site, submerging its remains.

Key Facts

StateNorth Dakota
LocationWashburn
Established1804
Decommissioned1806
War / eraOther / Unspecified
Current statusMuseum / Historic Site
Coordinates47.29805556, -101.0872222

Map

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🧳 Visiting

What you’ll see when you visit:

  • Reconstructed 1804-1805 Lewis and Clark winter encampment with period-accurate wooden structures
  • Interpretive exhibits on the expedition's historic winter stay and tribal relations
  • Walking trails along the Missouri River with views of the landscape the explorers encountered
  • Museum featuring artifacts and information about the Mandan, Hidatsa, and Arikara tribes
Best time to visitLate spring through early fall (May-September) offers mild weather; winter months recreate the season the expedition endured but present harsh conditions.
Getting thereFly into Bismarck Municipal Airport (BIS), approximately 64 km south of Washburn, then drive north to the site.
From the nearest major airportBismarck Municipal Airport (BIS)🚗 48 mi by road⏱️ ≈ 1 hr 11 min drive

Sources

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