Our ancestors were forced to evolve into ultra-runners, over time and as more travel became necessary to hunt prey that was constantly on the move. Almost 2 million years ago, ancient men would scoff at the proposition of running 100 miles - if scoffing had been a thing back then, of course. Regardless of their opinion on it, the fact remains that it was no physical problem.

But nowadays, ultra-runners are prime specimens and exceptions to the norm. No one actually needs to run that far for that long, but some simply want to...

The Leadville Trail 100 is commonly referred to as the "Race Across the Sky" and began in 1983. This out and back course takes you from it's lowest point of 9,200 feet to it's highest at 12,600 feet up on Hope Pass. Most of the run is done on forest trails and certain sections of mountain road. Lottery drawings for participation in 2017's race open December 1st through the 31st, 2016.

(Video Credit: Salomon Trail Running)

  "It gets to a point during a run like that, no matter how good an athlete you are and no matter how well trained you are, that it’s going to really hurt. And it’s going to transcend the physical and become about the mental..."

As one of the oldest ultamarathons in the world, The Leadville Trail 100 attracts all sorts of ambitious athletes looking to test their limits and break down barriers. In it's first year it had only 45 competitors and was originally organized as a way to bring more people to Leadville - a mining town that struggled when the mine was shut down. Today, the event has huge sponsorship, training camps, and many other events for athletes of all kinds.