Admin note: If you are attempting the Catskill 3500 footers on public land please use the Catskill 35ers route page. This route page, the Catskill High Peaks, is largely intended to be a historical record of Catskill 3500 footer thru-hike (Direttissima) FKTs that apparently made extensive use of private land. If you use private land to record an FKT on this route page, please obtain permission from the appropriate landowners.

The TransAm has been run for decades, and there were even races in the 1920s (the famous "Bunion Derby") and again in the early 1990s.  A web search will yield much history, here's a brief summary:  https://www.outsideonline.com/2129171/brief-history-run-across-america  The course is open, and of course evolves with development of the road system, but the end points are fixed:  City Hall in San Francisco and New York City Hall (note that the TransAm footraces were Los Angeles to New York).

William Johnson submitted this route which starts off Hwy 97 south of Oroville, WA, and ends on top of Mt Hull (4619'):

Dave Kofranek submitted this 8.5-mile off-trail loop (approx 2500' elevation gain):

This route loops Little Wildhorse Lake and Wildhorse Lake proper via their drainages.