Two pretty remarkable people are taking on a pretty impressive task. Both are about to tackle an amazing feat - seven marathons in seven days on seven different continents.
It's called the Triple 7 Quest.
"I hopped the next day as soon as I knew that was even something that was out there to be done and that had never been done before I was all in," said Dave Jones from Kentucky.
Jones is a former smoker who is now addicted to running. On Friday...he heads to Australiato take on the quest.
Also hitting the course is BethAnn Telford from Washington D.C. The 47-year-old was diagnosed with brain cancer back in 2005.
Despite the fact that she can't see out of her left eye and relies on a catheter because of bladder issues, she's also taking on this challenge.
Telford says she knows she won't be the first to cross the finish line, but that simply participating is much bigger than winning.
Her run also raises money for pediatric cancer research.
Runners take on Triple 7 Quest: 7 marathons, 7 days, 7 continents
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