Extreme Adventure Biking

For these bikers, potential peril exists in every curve of the road.

A Matter of Fog and Faith

Bolivia Adventure Bikers
Bolivia Adventure Bikers
Bolivia Adventure Bikers
Bolivia Adventure Bikers
Bolivia Adventure Bikers
Bolivia Adventure Bikers
Bolivia Adventure Bikers
Bolivia Adventure Bikers
Bolivia Adventure Bikers
Bolivia Adventure Bikers
Bolivia Adventure Bikers
Bolivia Adventure Bikers
Bolivia Adventure Bikers
Bolivia Adventure Bikers
Bolivia Adventure Bikers
Bolivia Adventure Bikers
Bolivia Adventure Bikers
Bolivia Adventure Bikers
Bolivia Adventure Bikers
Bolivia Adventure Bikers
Before the pavement ends and the rough road begins, there is one very challenging section: a 4-mile uphill ride at an altitude of almost 12,000 feet. You can hear the muscles in your legs scream for oxygen as you inch your way upward. Some bikers opted to sit this part out and ride up on the bus. (Jeffrey Kofman/ ABC News)
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