The former gold rush boom town Dawson City is the second checkpoint. The five teams leave Haida Gwaii and head into the heart of the Yukon but who will reach the checkpoint first?
The race is on again as the five pairs head south to the third checkpoint, the Rocky Mountain resort town of Banff. Which team will come in last place and be eliminated?
The teams head for the fourth checkpoint, the remote outpost of Churchill, on Hudson Bay. The only transport is a twice-weekly train, and they have just three days to catch it.
The pairs enter the sixth leg of the race. The next stop is in Quebec. Canada's most densely inhabited region will have to be navigated by the teams to reach the checkpoint.
Their journey started on Canada's Pacific coast 41 days ago. Now the teams have the Atlantic within their reach as they race to the seventh checkpoint at the seaside town of Liverpool, Nova Scotia.