Aaron Arrowsmith & J. Puke, A Map Exhibiting All the New Discoveries in the Interior Parts of North America (1802)

This map, created by English cartographer Aaron Arrowsmith, depicts all that was geographically known about the United States at the time of its creation in 1802. This is the fifth edition of the map, as it was continuously updated by Arrowsmith to reflect new discoveries about the geography of the United States. The map was the first to name the Rocky Mountains, and to include many of the rivers around the Rocky Mountains. Some of the rivers are illustrated as dotted lines because their locations were based upon accounts of Indigenous People rather than actual observations. On top of the topographical information included on the map are the locations of Native American tribes. This map was taken by Lewis and Clark on their famous expedition as it provided them with the most comprehensive and accurate information on the geography of the West available at the time. French and American representatives also likely used this map while negotiating the Louisiana Purchase in Paris because it gave the best known approximation of the Louisiana Territory.