Click on the map above to enlarge.
Then click AGAIN on the area you’d like to see closer — and it’ll get REALLY big!
Move around the super-enlarged map via the R side and bottom Windows “sliders”.
Source: National Park Service: https://www.nps.gov/carto/hfc/carto/media/LECLmap1.jpg

Map of the Lewis & Clark Expedition, 1804-1806

We generally followed the westbound path, shown in red.  Roads don’t necessarily stick to the banks of the Missouri — quite often you have to seek out overlooks with good views of the Missouri.  There is a long stretch in central Montana (the White Cliffs and the Missouri River Breaks) that is still a remote wilderness inaccessible to vehicles.  That said, there are abundant vistas and many outstanding interpretive centers that well convey the feel of the land and of the harrowing adventures the expedition experienced struggling into the unknown.