Mamba 100 - Memphis, TN

NOV
6-7
2026
A multi-distance trail ultramarathon in Memphis centered on a 14 mile loop of fast singletrack. Distances include 100 mile, 100K, 50K, and 25K with staffed aid stations and finisher buckles or medals.
6-7 Nov 2026
100 miles 62 miles 31 miles 16 miles

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Mamba 100

The Mamba 100 is a multi-distance trail event held at the Wolf River Refuge Trailhead on S. Walnut Bend Rd., Memphis, TN. The course is built around a roughly 14 mile loop of flat, fast, smooth single-track with a short lead-in section and a few small hills. Races repeat this loop multiple times to reach each distance.

Distances:

  • 100 Mile - 7 loops plus 2 mile start section, approximately 100 miles
  • 100K - 4 loops plus 6 mile start section, approximately 62 miles
  • 50K - 2 loops plus 3 mile start section, approximately 31 miles
  • 25K - 1 loop plus 1.5 mile start section, approximately 15.5 miles

Two fully staffed aid stations serve the course: Start/Finish at the Wolf River Refuge Trailhead and Walnut Grove Bridge, passed twice per loop. Aid stations provide water, electrolyte drink, soda, and standard ultra fare; drop bags are allowed only at the Start/Finish aid station. The 100 mile field is a Western States qualifier with a 34 hour cutoff to earn qualifier status.

Race rules require runners to complete the course on foot, carry their own gear (no muling), and follow marked course and crew access restrictions. Age minimums apply by distance. Packet pickup is held at the trailhead the day before the races. Official race photography will be provided and images are free for participants. Visit the organization's website for the most recent information.

100 mi
100 Miler
62 mi
100k
31 mi
50k
16 mi
25k