The Four Cache Sites

Museum display on how trappers packed caches.

Courtesy of Museum of the Mountain Man, Sublette County Historical Society, Pinedale, Wyoming.

The first cache site was east of the Continental Divide in the vicinity of the confluence of the Marias River and the Missouri. Several of the journal writers tell us a bit about the process which was under the direction of Pierre Cruzatte, who had experience building caches. It was June 9, 1805.

On higher and drier ground, a 20-inch-wide hole was cut in the sod, then a six- to seven-foot-deep hole was dug. Dried sticks and animal skins were used to separate and protect the items deposited into the earthen “safe.” This site’s cache included extra ammunition, axes, hammers, flour, pork, salt, chisels, tin cups, animal skins, beaver traps, and more. Most of all, the larger red pirogue was hidden – a few journal comments tell us it was pulled up onto a small island near the mouth of the Marias and secured to the trees to keep it from being carried off in the high water of the next spring.

The second cache site was near the lower portage camp where the white pirogue was hidden in the willows below the Great Falls and Lewis’ desk, some books, specimen of plants and minerals, kegs of pork, more ammunition, flour, two blunderbusses, and various personal items were placed in a pit. Also offloaded at this point was the swivel gun that had been mounted on the Corps’ keeled barge. Lewis wrote that they “deposited the swivel and carriage under the rocks a little above the camp near the river.” On July 10, a second pit at the upper portage camp was dug to hold Lewis’ experimental iron-framed boat along with some papers and a few other items.

In mid-August 1805, after a long and stressful search for the Shoshone people, the third cache was created near the Beaverhead River and site of Camp Fortunate. Knowing the journey now required horses to aid in the climb over the great divide, the men sunk their dugout canoes in the river and buried everything they knew couldn’t be hauled over the mountains. On August 21, 1805, Sergeant John Ordway wrote: “four men sent to dig a hole or carsh… this evening after dark we carried the baggage to the carsh or hole which we leave at this place. we took it to hide undiscovred from the natives.”

The final small cache was created in early October 1805, when camping with the Nez Perce people near the Clearwater River. Into the pit was placed several lead canisters of gun powder and some balls. Since the Corps would be soon returning to river travel, the Captains arranged for the Nez Perce to care for their horses until their return, and their saddles were hidden somewhere near the cache pit.