Pippa has done a lot of thorough research to make the story believable, and you can find how she did it here on The History Girls blog.
From Grandmama's house, they escape across the Atlantic by ship to Quebec and then by train across the Canadian prairies to the west coast where they get yet another ship up to Dyea at the start of the Chilkoot Trail. On the way, they meet helpful and not so helpful prospectors who serve to hinder their progress.
The real challenge comes when Ida and Fa have to provide a ton of goods to last them for a year. They make many trips to Pass Summit carrying it all on their backs and then build a wooden boat to sail to Dawson before they can even think about finding gold. Some of the story is told in letters that Ida writes to Grandmama, in the hope that they will travel the thousands of miles to England. But did they find gold? You'll have to read Finding Fortune to find out!
I'm not sure whether he followed the Chilkoot Trail or the White Pass to the south, but both routes were treacherous, and the pack horses that people bought were no use and often left by the trail where they fell.
We were able to ride on it on a trip to Skagway, Alaska. You can see how the train clings to the mountain side, and then rattles over the sort of trestle bridge you see in cowboy films, before entering a tunnel.
It made me think about the journey that he made over one hundred years ago, and the hardships he must have endured without the luxury of train travel.
The story goes that he did find gold, but spent it all on wine, women and song, despite how innocent he looks in the photograph!
Have you read Finding Fortune or travelled up the White Pass Railroad?