I've got the maps and they mention some gravel and dirt roads, but one's guys dirt road is another guys mountain bike route so I was hoping someone out there has actually ridden the route Adv Cycling mapped out.

And yes, by the way, Adventure Cycling does have a mountain bike route. The great divide route from Canada to Mexico is just such a route.

Thanks for the info. I'm thinking it will be a very pretty trip. I plan on taking lots of photos.