Runners battle rough terrain in what is called the toughest race in the world. Competitors race all day and night in a natural setting that can quickly turn ferocious and dangerous. It's the trail running race in Patagonia, Chile. Only 30% of entrants make it. A grueling 141-kilometer test of endurance. The astounding power hidden in the runners' muscles pushes beyond the breaking point, and they start to lose the sense of vision and even themselves. This is "God's Territory".