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In May, ultrarunners Joelle Vaught of Boise, Idaho, and Amy Sproston of Bend, Oregon, set out to cross Zion National Park. The roughly 48-mile route, known as the Zion Traverse (or Trans-Zion Trek) has become an iconic and contested fastest known time, or FKT.
This six-minute video, by Montrail and Sierra Studio Films, chronicles the adventure as the two women run below sandstone cliffs and through lush valley floors. Though Sproston dropped partway through, Vaught went on to set the FKT for the route: 8:26:09, six minutes faster than Bethany Lewis’s 2013 time.