William Clark, A Map of Lewis and Clark's Track across the Western Portion of North America (1814)

The engraver Samuel Lewis used William Clark's map of his famous westward expedition with companion Meriwether Lewis to create this version of the map, which accompanied Nicholas Biddle's 1814 History of the Expedition. It is considered one of the nineteenth century's most important cartographic achievements because it forever altered people's understanding of the West, including that the Missouri and Columbia river systems were not the navigable highways President Jefferson had hoped for and that the northern Rockies were actually a tangle of mountain ranges. By comparing the map with Arrowsmith and Lewis's 1804 map, also featured on this site, you can see substantial differences.