eographical lore from the time of the French explorers Marquette, Hennepin and LaSalle in the 17th century suggested that beyond a set of mountains in the western interior a great river flowed to the Pacific Ocean.

British cartography in the 18th century reinforced the early French imagery with the notion that a river with might equal to the Missouri flowed westward from shared heights.

Have fun exploring the details of these maps by taking advantage of the DjVu map viewer to see high resolution maps online.