Marsh Madness

AUG
7-8
2026
A free 32 hour ultramarathon at Pointe Mouillee State Game Area near South Rockwood, Michigan, on August 7 to 8, 2026. Alternating daytime 8 mile and 4.6 mile loops with a 4 mile nighttime loop; participants carry their own aid.
7-8 Aug 2026
8 miles 5 miles 4 miles

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Marsh Madness

Marsh Madness is a 32 hour ultramarathon held August 7 to 8, 2026, at Pointe Mouillee State Game Area near South Rockwood, Michigan. The course runs on dikes where the Huron River, the Detroit River, and Lake Erie converge.

The course uses alternating loops and segments:

  • 8 mile loop along the dike
  • 4.6 mile out and back
  • 4 mile loop for late night hours

Course and race details: elevation gain is 69 feet per loop. Surface is approximately 80% gravel and 20% asphalt. There are zero water crossings. Porta potties will be on the 4.6 mile out and back. Access to a vehicle is possible approximately every 8 miles.

Field and support: the event is limited to 50 runners. Participants must supply all of their own aid and nutrition; crew, pacers, and poles are permitted. There are no official cut off times. The dike cannot be run between 11 pm and 6 am and a nighttime course is planned. No garbage cans are provided; participants are expected to pack out their trash. Registration is free and runs from April 6, 2026 to August 6, 2026. Visit the organization's website for the most recent information.

8 mi
Day Loop
5 mi
Out-and-Back
4 mi
Night Loop
Marsh Madness 32-Hour Ultramarathon
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