Astride the Montana-North Dakota border, standing proud atop the banks at the confluence of the Yellowstone and Missouri Rivers, the Fort Union Trading Post National Historic Site was once the largest and busiest outpost on the upper Missouri River. Despite the “fort” in its name, it was never a part of the U.S. military; it was, however, the most successful and longest-lived of all the frontier trading posts. In 1804, Lewis and Clark visited the site, which they called “a judicious position for the purpose of trade.” Twenty-five years later, John Jacob Astor’s American Fur Company proved them right, establishing an outpost here in a successful attempt to end the Hudson Bay Company’s monopoly on northwest trade. Linked by steamboat with St. Louis some 1,800 miles away, Fort Union reigned over the northern plains. Its bon vivant overseer, Kenneth McKenzie, the “King of the Missouri,” kept the fine china polished and the wines cool in the cellar, offering a taste of displaced civilization to such luminary explorers as George Catlin, Prince Maximilian, and John James Audubon.
The fort was abandoned as the fur trade declined in the 1850s, and portions of original buildings and walls were taken down by the U.S. Army in 1867 to construct Fort Buford, a mile to the east. In the late 1980s, the National Park Service reconstructed the buildings atop the original foundations, giving a palpable if somewhat overly polished idea of how the old fort looked. McKenzie’s old home and office, Bourgeois House, is now a visitors center (701/572-9083, daily, donation) with some surprising artifacts. The fort hosts occasional reenactments of boisterous frontier life: Mid-June, for example, brings the annual Fort Union Rendezvous, a rollicking re-creation of fur-trapper gatherings to trade, talk, and compete in wilderness skills.