Mamba 100 - Memphis, TN
Memphis, United States • 7-8 Nov 2025
Event overview
The Mamba 100 takes place November 7-8, 2025 at the Wolf River Refuge Trailhead on S. Walnut Bend Drive near Memphis, TN. Distances offered:
- 100 Miler
- 100K
- 50K
- 25K Registration closes Monday, November 3, 2025 at 11:59 PM CT.
Course and logistics
The course is a 14.35-mile loop along the Wolf River, made up mostly of single-track trails with low elevation gain. Distances require multiple loops: the 100 miler is seven loops, the 100k is four loops plus a shorter starter loop, the 50k is two loops, and the 25k is one loop. There are two staffed aid stations: Start/Finish at the trailhead and Walnut Grove Bridge, which is passed twice each loop. Drop bags are permitted only at the Start/Finish aid station. Packet pickup takes place at the Start/Finish location; during pickup runners may set up 10x10 canopy tents for crew use.
Rules, pacers and awards
The 100 miler is a Western States qualifying race. Pacers are permitted for the 100 miler and 100k only; no pacers for the 50k or 25k. One pacer at a time is allowed and pacers must sign a release and wear a pacer bib. Pacers may not carry gear for their runner outside fully manned aid stations. Top three male and top three female finishers in each distance receive an award plus a buckle or medal. The race is Trail Sisters approved. Visit the organization's website for the most recent information.