A rails to trails route that is a 298.1 mi point-to-point. When fully completed the Northeast Texas Trail (NETT) will be the longest Hike/Bike and Equestrian Trail in Texas and one of the longest in the U.S.A.

100+ miles across Big Bend National Park.

The route begins with 50-mile traverse of the 311,000 acre Big Bend Ranch State Park. Hikers cross the Mesa de Anguila and approach the Chisos from the West, concluding the trip on the South Rim, Texas' pride and joy. This route offers exceptional navigational challenges. Expect off-trail navigation hazards through rarely traveled remote sections of these parks.

Route breakdown: trail=49 mi, dirt road/4WD roads=29 mi, sandy arroyo=14 mi, off-trail route finding=5 mi, paved road=3 mi

Scott Gilpin proposes starting / finishing an FKT at the Teatro Juarez in Guanajuato:

Starting from in front of Teatro Juarez, run to the cross at the top of "La Bufa", and return to your starting point. There are many possible variations - the posted GPX is what I found to be most efficient for myself. Others may find better options.

Cerro de Sirena (2404m) is the highest of the hills surrounding Guanajuato, in central Mexico.  For the FKT, start in front of Teatro Juarez, run to the cross at the top of "La Sirena" (about 3km, 480m gain), and return to your starting point. There are many possible variations.

Wild Basin is a huge drainage in Colorado's Rocky Mountain National Park. Hikes to the peaks at the head of the Basin always entail long approaches, usually 18+ miles round trip. It is aptly named: everything in Wild Basin is remote.

The "rules" for ridge traverses such as this are simple: You don't have to stay exactly on top of the ridge at all times, you just have to tag all named and significant summits along the way.  It seems logical to require that one close the loop, which requires roughly 30 miles of travel.