It's the "Continental Divide Trail" that runs from the US/ Mexico border up into Canada.
Total length is 3,200 miles and crosses New Mexico, Colorado, Wyoming, Montana and up to Banff.
This trail was originally set up for bicycles and hikers and some sections do not allow motorized travel so people have gotten a little creative with the routes.
The route selected came from GPX files made by GPS Kevin and this one was about 85% dirt roads with some technical sections thrown in.
2010 Subaru WRX
1970 Greeves Griffon 250