On June 29, 1806 the Corps returned to Montana and took a well-deserved soak in the Lolo Hot Springs and later regrouped at nearby Travelers' Rest to plan the next phase of the journey. From here the expedition split into two smaller parties. Lewis and nine men returned up the Missouri on July 3, 1806 to further explore the Marias:
"All arrangements being now completed for carrying into effect the several schemes we had planned for execution on our return, we saddled our horses and set out. I took leave of my worthy friend and companion, Captain Clark, and the party that accompanied him. I could not avoid feeling much concern on this occasion, although I hoped this separation was only momentary."
Clark took the rest of the men and the Charbonneau family to chart the Yellowstone River. The entire Corps was to reunite at the mouth of the Yellowstone for the return trip to St. Louis.
The following are a few of the stops in the journey: