William Clark`s Map of the Lewis and Clark Trail
The Split Into Subgroups
On Google Maps.
Clark's map with overlays added by myself.
Eager to explore as much of the newly acquired Louisiana Territory as possible, the captains agreed to split into subgroups on the return trip eastward. This plan was implemented after making it back through the Rocky Mountains and reaching Travelers Rest.
[1] At Traveler's Rest Lewis takes one group due east, following a trail the Nez Perce would use annually to hunt bison. Nez Perce territory was west of the Rocky Mountains, and bison were only to be found on the eastern side. Clark takes his group due south, along a route similar to the one taken by the expedition on the westbound journey.
[2] At the head of the Jefferson River, Clark's group retrieves canoes cached on the westward trip. They take the canoes down the Jefferson River to Three Forks.
[3] At Three Forks, Clark's group splits into two subgroups. A subgroup led by Sergeant Ordway heads north, taking the canoes down the Missouri River to the Great Falls. Clark takes his subgroup eastward, to cross overland to the Yellowstone River.
[4] Clark's subgroup crosses the Continental Divide at Bozeman Pass. They're guided through the Bozeman Pass by Sacagawea, who grew up in this region.
[5] Clark's subgroup makes canoes, then proceeds down the Yellowstone River.
[6] Clark carves his name into the face of a sandstone butte, and names the place Pompey's Pillar. This signature is the only remaining physical evidence of the Lewis and Clark Expedition.
[A] At the Great Falls, Lewis leaves a few men to wait for Sergeant Ordway's subgroup to come down the Missouri River. While Lewis explores the Marias River, the Great Falls is portaged by this unified group.
[8] Lewis reaches what seems to be the northernmost point of the Marias River, and makes celestial observations in order to fix his latitude. The extent of the Louisiana Purchase was defined by the US as the entire drainage into the Mississippi River from the west, and the purpose of this exploration was to determine the northernmost extent.
[9] Lewis's group encounters a band of Blackfoot Indians in the heart of their territory. A minor skirmish ensues, and Lewis returns at top speed to the remainder of his group, who are waiting on the downstream side of the Great Falls.
[7] Lewis's group and Clark's group reunite at the confluence of the Missouri and Yellowstone Rivers, and the expedition returns down the Missouri to St. Louis.
