So far the team have travelled just thirty of the nearly six hundred mile journey to the gold fields. Having made their way across the Alaskan Coastal Mountains they now face a very different challenge: the treacherous Canadian Lakes and rivers.In tonight's episode Dan and the team begin a marathon boat trip. They'll be travelling in a specially built replica wooden boat based on original designs from the gold rush. It's basic, heavy and difficult to control but somehow they're going to have to navigate it across hundreds of miles of water. They'll face enormous lakes, notorious for unpredictable stormy weather and "One Mile Rapids"- a narrow canyon filled with churning white water and jagged rocks that wrecked dozens of the Klondiker boats. No one has attempted to run these rapids in a boat like this over a hundred years.