The Mackenzie River originates in Great Slave Lake and flows north into the Arctic Ocean. It is the longest river in Canada at 1800 km in length and part of the second-largest river system in North America after the Mississippi-Missouri system.

The Mackenzie River system includes:

  • Great Bear Lake
  • Great Slave Lake
  • Athabasca Lake
and the following rivers:
  • Arctic Red
  • Athabasca
  • Liard
  • Peace
  • Slave
  • South Nahanni

The large marshy delta of the Mackenzie River provides habitat for migrating Snow Geese, Tundra Swans and Brant as well as breeding habitat for other waterfowl. The estuary is a calving area for Beluga whales.

The Mackenzie was named after Alexander Mackenzie who travelled the river while trying to reach the Pacific Ocean.