Ambrose did a good job of pulling together all the information from the different journals of Clark, Lewis, and the other men to put together an upbeat and facinating story. The reader is pulled along in a way that we share Ambrose's frustrations as the known facts are such that we have to speculate as to what exactly happened or what one was thinking at a certain point. Also what Ambrose does a good job of doing is analyze the historical happenings of the time and relating them to the story and how they affected the journy.
The last 50 pages offered a real disapointment. This dealt with the story after the celebration and meeting with Jefferson. In these chapters we see the downward slope of Meriwether Lewis's life. I felt that Ambrose should have rapped this up in a couple pages, but instead it became depressing and lacked the adventure of the previous chapters.
All in all the book was pretty good, disregarding the beggining and end. Anyone who craves adventure or loves american history is compelled to read this book.