Lewis & Clark and the Corps of Discovery: Where They Went, Who They Met, What They Traded

the mission and Jefferson's orders, both captains' stories, the full roster with where everybody was from, the whole route with dates, every tribe they met and what happened (including the scary standoff with the Teton Sioux and the only fight of the trip), what they traded going both ways, what became of everybody afterward, and a page of odd bits — like the prairie dog that lived in the White House.

My favorite part: Sacagawea finding out the Shoshone chief selling them horses was her long-lost brother. Without those horses, the expedition ends in the Rockies.