Here is something new -- and hard. The Idaho Boundary Trail circumnavigates the state of Idaho for 2400 miles. It includes portions of the Idaho Centennial Trail, the Continental Divide Trail, and Hells Canyon. Plus a lot of other empty country. It is 50% dirt road with the remainder being trail or imaginary trail. The route has been ground truthed and is documented in great detail by the two guys who came up with the idea and survived attempts in 2012 and 2013.
As a bikepacking route, the trail needs some modifications to get around the Wilderness Areas and the too-crazy-to-try bits. Scott and Eszter have already staked out some of the evil areas along Montana-Idaho border (
http://topofusion.com/diary/cdt-2014-diary/). The blog associated with the Idaho Centennial Trail (
http://idahocentennialtrail.blogspot.com/) may provide some advice on how to navigate that messy area along the northeast leg.
Who is willing to take first crack at this on a bike?
Try these links for starters:
http://fultek.com/ibt/IBT%20Hiker%27s%20guide%202015.pdfhttp://www.fultek.com/ibt/http://www.trailjournals.com/about.cfm?trailname=14919