A publication of the Archaeological Institute of America
The journals of Meriwether Lewis and William Clark indicate that their 33-member expedition camped at more than 600 sites on its 28-month trek from St. Louis to the Pacific Ocean, none of which has ever been found. Archaeologist Ken Karsmizki of the Museum of the Rockies at Montana State University in Bozeman is investigating four potential sites in three states. "Most of the Lewis and Clark camps were used for a single night, and then the expedition moved on," says Karsmizki. "Winter campsites were occupied for much longer periods and therefore would have a better-developed archaeological record, which should be easier to identify."
Funding from Kampgrounds of America has allowed Karsmizki to study one of the sites, marked by the remains of 12 fires, at the Lower Portage of the Great Falls of the Missouri River in Montana. The explorers' journals tell of 12 days spent at this camp. "Three of the fires were found equally spaced in a line, suggesting an organized campsite," says Karsmizki. "Archaeomagnetic dates from the charred remains are consistent with a Lewis and Clark occupation. We've also radiocarbon dated a broken-off wooden stake uncovered upright in the soil to 1810 ± 40, and bison bones from the site to 1810 ± 50." Members of the party prepared a large quantity of dried fish, meat, and pemmican (dried bison meat mixed with fat), while camping at Great Falls. Karsmizki plans to add a fifth site, one that may yield remains of a collapsible iron-frame boat that the party abandoned at the Upper Portage of the Great Falls because they lacked materials--pine pitch and needles for sewing hides together--necessary for making the vessel watertight.
Another Lewis and Clark occupation site is at the Fort Clatsop National Memorial in northwestern Oregon, where the expedition camped for 106 days during the winter of 1805-1806. The investigation of this site is directed by senior archaeologist Jim Thomson of the National Park Service. Here Karsmizki and Annalies Corbin, also of the Museum of the Rockies, have assisted in the hunt for traces of a square wooden fort. A cast-brass bead found at the site is known to have been manufactured between 1793 and 1820, consistent with the date of the expedition. The lead of a musket ball from the site has been traced to a lead-zinc mining region in southeastern Missouri. Historical research at the National Archives is attempting to determine if the expedition purchased lead produced in this region. Samples from a possible privy pit at the Fort Clatsop site were sent to the University of Wisconsin and the University of Washington for analysis. The explorers' journals indicate that most of the men were suffering from syphilis and being treated with doses of mercury, which the body then excretes. Traces of mercury in the privy samples would strengthen the latrine's association with the expedition.
Early in their travels, during the winter of 1804-1805, Lewis and Clark stayed for 150 days at Fort Mandan, on the Missouri River in central North Dakota, named for the nearby village of Mandan Indians. Here French-Canadian fur trader Toussaint Charbonneau and his Shoshone wife Sacajawea were hired as interpreters. In conjunction with the North Dakota Lewis and Clark Bicentennial Foundation, Karsmizki plans to investigate a possible Fort Mandan site, identified by a comparative analysis of Lewis and Clark's maps, others from 1855, the 1880s, and the 1890s, and aerial photographs. The next phase of the search will involve a magnetometer survey of several acres.
Two years after their journey was completed, Lewis and Clark invested in Fort Ramon, a fur trading post on the Yellowstone River employing five former members of the expedition as trappers. Karsmizki believes the traders may have modeled the settlement after Fort Clatsop. Karsmizki, Corbin, and graduate student Crystal Bauer surveyed four acres that revealed magnetic anomalies possibly associated with the fort. Archaeological testing is under way, funded by the Charlie Russel Riders, a private group interested in Western history.