BOULDER - The world's largest Ironman Triathlon took place in Boulder on Sunday.
Athletes began the race at 6:20 a.m. on Sunday at the Boulder Reservoir for the swimming portion of the event. They swam 2.4 miles and biked for 112-miles to Boulder High School.
From there, the entire marathon - which is 26.2 miles.
To earn "Ironman status," athletes must finish the triathlon by midnight.
Learn more about the Ironman here: http://bit.ly/1pLpcnD
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