The OSS/CIA 50 miler is (as its name suggests) a 50 mile event.  The course is a 25+ mile loop run primarily on single track, with some fire road, and several bridge and road (NPS road) crossings.

The 25+ mile loop is run twice to give you 50+ miles. Starting in 2023, we will incorporate a night marathon into the fray. It will start at 11:55p.m.. This will give athletes 8 hours and 35 minutes to complete the one loop event. All cut-offs in place for 50 mile will be incorporated into the night marathon.