Soon they were traveling in deep snow. The men couldn't find their way, so they returned to the Nez Perce for help and native guides. At this second attempt they managed to cross the Rockies without further difficulty.
Once over the Continental Divide, on June 30 Lewis and Clark decided to take separate routes for a while in order to explore more of the Louisiana Territory. Lewis and nine men went to explore the Marias River to the north, while Clark and the others went to the Yellowstone River in the south.
