Originally, the run was conceived as being between the lowest and the highest points in the contiguous United States, the Badwater Ultramarathon is described as "the world's toughest foot race". It is a 135 mile course starting at 282 feet below sea level in the Badwater Basin, in California's Death Valley, and ending at an elevation of 8360 feet at Whitney Portal, the trailhead to Mount Whitney.
The race begins on July 23, when the weather conditions are most extreme and temperatures over 120 F in the shade are not uncommon. Consequently, not many people—even among ultramarathoners—are capable of finishing this race.
For more information visit: Badwater Ultramarathon