The Corps of Discovery reached the Pacific coast in November 1805 after traveling through homelands of many Native nations. Meriwether Lewis and William Clark selected a winter site south of the Columbia River within Clatsop territory, near food, timber, freshwater, and river access. Members constructed a small log stockade in December and named it Fort Clatsop. The party included soldiers, civilian interpreter George Drouillard, York, an enslaved Black man, Sacagawea, her infant Jean Baptiste, and Charbonneau; their authority and experiences within the expedition differed profoundly.

The group occupied the fort for about three wet months, from late December 1805 until 23 March 1806. Rooms surrounded a compact parade area and held officers, enlisted men, families, storage, and workspaces. Expedition members hunted elk, made salt near the coast, repaired equipment, sewed moccasins, prepared specimens, copied journals, and mapped their route. They traded with Clatsop and Chinookan people for food, canoes, information, and goods, but relations included mistrust, unequal expectations, and the expedition's taking of a Clatsop canoe shortly before departure.

Lewis and Clark left the structure to Clatsop leader Coboway, and the damp log building deteriorated rapidly. Later settlers identified a traditional location, but no confirmed standing timbers or unambiguous structural remains survived. Private owners and civic organizations commemorated the area, and federal protection began in the twentieth century. A reconstructed fort was completed in 1955 using William Clark's floor plan, journal descriptions, period tools, and educated interpretation. Fire destroyed that replica in 2005; the National Park Service built the present reconstruction on the same commemorative site in 2006.

The current stockade is thus a reconstruction of a reconstruction, not original expedition fabric and not proven to occupy every wall line precisely. Furnishings, bunks, hearths, demonstrations, and costumed programs help visitors understand cramped winter life but necessarily select among uncertainties. Archaeological investigation continues to examine the surrounding area. The broader landscape—river, wetlands, forest, trails, and connections to the coast—provides genuine geographic context, although modern vegetation, roads, drainage, buildings, and restored habitat differ from 1805 conditions.

The National Park Service manages Fort Clatsop within Lewis and Clark National Historical Park, which links multiple sites in Oregon and Washington and works with affiliated tribes. Admission and passes apply under current park arrangements, with a visitor center, trails, canoe landing, replica, and programs available subject to hours and weather. Accurate interpretation avoids calling the cabin an original fort and places the expedition within Native homelands rather than an empty wilderness. Its significance lies in the documented winter encampment, Indigenous encounters, national expansion, environmental setting, and the evolving public reconstruction of an absent building.