Michael Portillo embarks on a second spectacular rail journey through Alaska to Canada. A dog musher tells Michael how huskies helped to build Alaska.

At Fairbanks, Michael discovers how gold prospectors liberated precious metal from the soil.

Michael travels north to explore the remote former goldrush settlement of Talkeetna.

In Anchorage, Michael prepares to join the US Arctic Warriors for parachute training.

Michael Portillo heads for the Last Frontier of the United States. In Seward, Michael feeds a rescued sea otter pup.