The United States is on a path to what could become the largest official bicycle route network in the world, thanks to the approval of a new plan by America’s leading authority on national route designations. The American Association of State Highway and Transportation Officials (AASHTO) has just approved a National Corridor Plan laying out the framework and guidelines for the development of this system.
"The plan -- under development over the last four years -- identifies corridors connecting America’s urban, rural, and suburban areas. The corridors cover well over 50,000 miles, which, if transformed into routes along roads and trails, would create the largest official bicycle route network in any country or on any continent. By comparison, the planned Euro-Velo network in Europe is projected to be 60,000 kilometers or 36,000 miles..." (from National Center for Bicycling and Walking)