Thanks, David. What a journey that would be to do with your son! For sure you could get lots of advice and support here. Trips of that kind can be wonderful, and shape a lifetime. When our son was a teenager, he and I spent a week hiking in Kluane, and that trek played a big part on restoring balance and affection into our relationship, which had been strained by tensions between dad and teenaged son. (Rebuilding an old ex-comp motorcycle together played a big part too.) Our daughter and I have always had an easier relationship--in part, because we've done a lot of hiking, canoeing, and now cycling together, & in some pretty special locales: Malawi, Namibia, Spain, Denmark, the Canadian Shield, etc.
Thanks also for the info on the Myra Canyon trestles. I was thinking of (the?) one that used to be advertised as the longest wooden trestle in the world -- I didn't realize that fire had destroyed so many. (We were living in South Africa between 2003 and late 2006, so missed a lot of information about Canada in those years.)
I have a clutch of old friends in Nelson, whom I'd visit on my mountain-trip-in-the-making; and my wife and I have an old friend who inherited her parents' farmhouse in the Okanagan just east of Vernon, off Hwy 6, and we'd plan to rendez-vous there as well. There are the usual variables of time-on-the-road and time-of-year to be juggled, of course, but I've thought of taking the train from Ottawa to Jasper, then cycling south from there for a month or more.