OSS/CIA 50 Mile Night Run

Triangle, United States • 13 Jun 2026

The OSS/CIA 50 Mile Night Run is a challenging ultramarathon held in Prince William Forest Park, Virginia, a historic site once used to train World War II OSS spies, predecessors to the CIA. The race features a 50-mile distance composed of two laps on a 25+ mile loop primarily on single-track trails, fire roads, and several bridge and road crossings. The event includes a night marathon option starting late at night, allowing runners to complete one loop within a set time. Aid stations are strategically placed, and crews are restricted to the start/finish area for safety. The course offers a unique blend of natural beauty and historical significance. Visit the organization's website for the most recent information.

Race information

50 mi
50 Miler
25 mi
25 Mile Night Marathon
Visit the organization's website for the most recent information.
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