In July of 1806, Meriwether Lewis and a small group of men from the Corps of Discovery main party, traveled eastward from Travelers Rest Camp, following the main Indian trail up the Big Blackfoot River in Montana. On July 5, they crossed the Clearwater River. This document reports on the research for the location of the trail and crossing that they used. The crossing by Russell is based on the Journal accounts. The crossing by Cox is based on a wagon road swale found by field exploration. The crossing by Bergantino is based on his research map of the area. For purposes of interpretation of Lewis & Clark, one of the crossings by Russell or Cox should be used.