Alexander Mackenzie
A Map of America, from Latitudes 40 and 70 North, and Longitudes 45 and 180 West, exhibiting Mackenzie's Track from Montreal to
Fort Chipewyan & from thence the North Sea in 1789 and to the West Pacific Ocean in 1793
London 1801

In 1789, from his headquarters at Fort Chipewyan on Lake Athabasca, Mackenzie set out, journeying north up the Slave River, across the Slave Lake, and then northwest along what has since been known as Mackenzie's River, finally reaching the Arctic Sea.  Despite discovering and describing a route to the Arctic Sea and territory completely unknown to Europeans at the time, he was disappointed not to find the Pacific Ocean.  Resolving to try again, he set out in 1793 with one other European companion and a small band of Chippewa Indians.  This map shows their route west from Lake Athabasca to the Pacific.