Get familiar with the Badwater Ultramarathon, 'the world's toughest footrace'

By JOHN DORN

Surely you're familiar with popular marathons like the ones in New York, Boston and various other large cities across the nation. But one lower-profile footrace makes those exhibitions seem trivial -- and you probably haven't even heard of it.

The Badwater Ultramarathon is a 135-mile race that ends roughly 8,500 feet higher than where it starts. Taking place in California's Death Valley in the heat of the summer, temperatures routinely rise near 120 degrees Fahrenheit.

The fastest-ever finish was recorded in 2007 by Brazilian Valmir Nunes, who crossed the tape at 22:51:29. Over recent history, about 70 to 80 people choose to compete in the race. Twenty to 40 percent of racers typically fail to finish.

The race is underway in California, and it's sure to be a grueling day for each and every participant. Temperatures are already creeping toward the 120 mark. Scroll through some shots of the trail from social media below.

Check out some more Badwater shots from years past in the gallery below.

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