ver Cuevana 3. This short documentary tells the story of one of the world’s most difficult and bizarre sporting events: The Barkley Marathons. This 100-mile footrace and its 60-hour time limit force athletes to run, crawl and climb an elevation gain equivalent to two treks up Mt. Everest. In nearly thirty years, only fourteen runners, out of over one thousand participants, have finished The Barkley.