Yeah, you would have to do a ton of conditioning before your horse would be ready to make a trip like that. If it were me I would start conditioning my horse 2-1 1/2 years beore the trek actually began.
I'm thinking that it'll be next spring before I'll have them ready to go. Of course, that is assumming that both of them can hold-up to the conditioning.
I've about decided that I'll need a different saddle than the one that I normaly use. And there's the pack-thing which both my mare (and myself) still need to learn about......plus a gazillion other things, some of which I probably haven't even thought of yet.
But we'll get there. A guy can accomplish a lot in a year.
The good news is that the weather has broke, the grass is growing again and we are all in good health.