Extreme Marathons

Approximately 3,500 runners from 35 different nations compete along a 26.2-mile course that climbs 5,960 feet in elevation.
Lukas Lehmann / Keystone / AP

Jungfrau Marathon, Interlaken, Switzerland
Approximately 3,500 runners from 35 different nations compete along a 26.2-mile course that climbs 5,960 feet in elevation.

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