Mamba 100

The Mamba 100 is where endurance athletes come to test their limits on the cleanest, fastest dirt trails in the Southeast. This Western States Qualifier draws runners from across the country to tackle the legendary Wolf River singletrack, chase new PRs, and earn all-new 2026 buckles and medals, including the coveted Sub-20 and Sub-24 hour 100-mile buckles. With world-class photographers capturing every moment, seamless course marking, unmatched community support, and a race weekend that feels more like a celebration than a competition, the Mamba 100 is the event you’ll talk about all year. Registration opens Black Friday at Noon — and for 12 hours only, you’ll lock in the lowest price of the year. Claim your spot and experience one of the Southeast’s most exciting ultras.

Western States Qualifier Race

Mamba 100 Miler is officially a Western States Qualifying Race.
To earn your WSER qualifier, runners must complete the full 100 miles within the 34-hour cutoff.

Packet Pickup

Packet Pickup for the Mamba 100 will be held Thursday, November 5th at the Start/Finish line located at the Wolf River Refuge Trailhead on S. Walnut Bend Dr., Memphis, TN 38120, from 2:00 pm to 7:00 pm (CT).
During this time, runners may also set up their 10x10 canopy tents for personal aid stations and/or crew use.
Please remember: do not leave any food out overnight. Deer, raccoons, and armadillos will happily turn your supplies into their own late-night buffet.

Refunds, Transfers, and Deferrals

NO REFUNDS
NO BIB TRANSFERS

Entry can be deferred for 100% race credit if requested at least 6 months prior to race day.
Entry can be deferred for 75% race credit if requested at least 4 months prior to race day.
Entry can be deferred for 50% race credit if requested at least 2 months prior to race day.
Entry can be deferred for 25% race credit if requested at least 2 weeks prior to race day.

NO DEFERRALS 2 WEEKS FROM RACE DATE. NO CREDIT WILL BE GIVEN.

Dates and Times

100 Mile - Friday, November 6, 7:00AM
100k - Friday, November 6, 7:00PM
50k - Saturday, November 7, 7:00AM
25k - Saturday, November 7, 9:00AM

Course Description

The Mamba course is centered around a 14-mile loop of flat, fast, and smooth single-track with just a few small hills. Every race starts with a short “lead-in” section before runners enter the main loop.
Race Distances & Loop Breakdown
100 Miler - 7 loops + 2-mile start section / Total ≈ 100 miles
100K - 4 loops + 6-mile start section / Total ≈ 62 miles
50K - 2 loops + 3-mile start section / Total ≈ 31 miles
25K - 1 loop + 1.5-mile start section / Total ≈ 15.5 miles

Mamba 100 video

Aid Stations

This race features two fully staffed aid stations:
-Start/Finish – Wolf River Refuge Trailhead
-Walnut Grove Bridge – Runners will pass this aid station twice per 14.3-mile loop

Aid stations will be stocked with water, electrolyte drink, soda, and standard ultra fare. Offerings may vary, but we’ll do our best to accommodate dietary restrictions.
Drop bags are permitted at the Start/Finish Aid Station only.

100k first 6 miles

100 miler - first 1.8 miles

50k - first 3 miles

25k - first 1.5 miles

Awards, Medals, and Buckles

• Top 3 Male & Female in every race distance receive awards.
• 100 Mile:
– Sub-20 Hour buckle
– Sub-24 Hour buckle
– All 100-mile finishers earn a custom Mamba buckle
• 100K: All finishers earn a 100K buckle
• 50K & 25K: All finishers earn finisher medals
All buckle and medal designs are brand-new this year.
Note: We do not offer drop-down buckles or medals for any distance. Every award is earned for the race you complete.

14 mile loop

Locations

The Mamba 100 is held at the Wolf River Refuge Trailhead on S. Walnut Bend Rd., Memphis, TN 38120. This is also the location for Packet Pickup on Thursday, November 5th from 2:00–7:00 pm.

The trailhead sits just off Germantown Parkway, directly across the street from the Shell Gas Station and Lowe’s, making it easy and convenient to find.

Race Rules

Mamba Trail Runners — Race Rules
Every runner is responsible for knowing and following all rules.
These are standard ultra rules — not overly restrictive.
Most issues happen from misunderstanding, not cheating.

General Race Rules
No dropping down in distance during the race.
No muling — runners must carry their own gear, food, and water.
Crew can only access their runner at the Start/Finish line area.
Crew may not assist or access their runner anywhere else on the course.
Trekking poles are allowed — be courteous around others.
Pacers must run the entire 14-mile loop with their runner.
Pacers and crew must follow all rules — see “Aid Station & Pacers” for full details.
No littering at aid stations, on trails, or at the finish line.
No course cutting or shortcuts — stay on the marked course.
If you don’t follow the course as marked, you will not receive an official time or award.
Race must be completed on foot only (no bikes, scooters, skateboards, roller skates, vehicles, sled dogs,).
Headphones are allowed, but remove them when approaching aid stations.
Be respectful when runners approach to pass — stay aware of your surroundings.
You are responsible for the behavior of your crew and pacers.
Rude or disrespectful behavior toward volunteers, staff, other runners, hikers, or cyclists can result in disqualification.
If you receive an IV, oxygen, or have a serious injury, your race is over.
Drop bags are allowed at the Start/Finish line area only.
No stashing of supplies along the course — use official drop bag location only.
No cheating. If you have to ask if it’s cheating… it probably is.

🧍 Age Requirements
100 Miler: 18+
100K: 18+
50K: 16+ (Parent/Guardian must sign waiver)
25K: 13+ (Parent/Guardian must sign waiver)

Sponsors

We would love for you or your company to sponsor the Mamba 100. We have many different types of sponsorships available. Please reach out to mambatrailrunners@gmail.com if interested. Sponsoring the race will guarantee you a 10x10 canopy tent spot right by the Start/Finish line of the race.

Pacers

Pacers are permitted for the 100 miler and the 100k distances only.
-No pacers allowed for the 50k and 25k distances.
-One pacer at a time per runner
-Pick-up location: Pacers may only begin from the Start/Finish Aid Station and run the entire loop with their runner.
-100-mile runners: Pacers may begin at Loop 4.
-100k runners: Pacers may begin at Loop 3.

Pacer Rules:
-Pacers must sign a release form and pick up a pacer bib at packet pickup or before their pacing duties.
-Pacer must stay with their runner at all times.
-Pacers must enter and exit with their runner at all times (aid stations)
-No muling: Pacers may not carry water, food, lights, or gear for their runner.
-Pacers may receive aid at aid stations and carry their own supplies.
-If a runner drops, the pacer must stop as well.
-In case of emergency, a pacer may leave a downed runner only to seek aid at the next aid station. The runner will be withdrawn from the event for safety.
-Pacers are companions - not leaders. Runners are responsible for navigating the course.

Drop Bags

Drop bags are only permitted at the Start/Finish line area. For runners who don’t have their own personal canopy, we’ll have a dedicated 10x30 grey “Runners Tent” set up for you. You’re welcome to place your gear inside and access it after each 14-mile loop. This space will be covered, easy to find, and open throughout the race to keep you organized and moving strong.

Photographers

We’re bringing in two of the absolute best.
Jenny Thorson and Misty Herron will be the official photographers of the race, capturing every gritty, joyful, and unforgettable moment. These two are masters of their craft—their work has been featured in major publications, ultra-running magazines, and more.
And the best part? Every single photo from the race is 100% free for all runners to download, share, and keep.
Get ready for world-class photos that tell the full story of your race experience.

Accommodations

The Wolf River Refuge Trailhead (start / finish line) is located right off Germantown Parkway and there are numerous hotels, restaurants, grocery stores, gas stations, etc. all along Germantown Parkway. Everything you can possibly need is within a mile or two from the Trailhead.

Holiday Inn Express & Suites 7784 Wolf Trail Cove Germantown, TN 38138 (901) 309-6700
Courtyard Memphis/Germantown 7750 Wolf River Blvd. Germantown, TN 38138 (901) 751-0230
Homewood Suites 7855 Wolf River Blvd. Germantown, TN 38138 (901) 751-2500
Hampton Inn & Suites 1680 S. Germantown Rd. Germantown, TN 38138 (901) 309-0555

RV camping is also available at Agricenter International. The RV Park offers sites with sewer, 30-amp & 50-amp electrical hook-ups, water, dump station, restrooms, shower, and laundry facilities. The RV Park at Agricenter is the perfect location if you plan on bringing or renting an RV. The main car parking area for Viper is right across the street from the RV campground.Walmart and grocery stores are ~2 miles away.

Restaurants - There are many restaurants packed up and down Germantown Parkway

Breakaway Running Store - less than a mile away for all your running needs and gear

Trail Sisters Approved Race

Mamba 100 is a Trail Sisters Approved race — meaning every athlete can count on equal opportunities, equal podiums, equal swag, and a fully supportive race environment for women at every distance.

Crew / Personal Aid Station rules

No dog pens allowed.
No open camp-fire flames. Solo stoves are allowed.
No loud music at any time.
Canopy tents should be 10x10. Please don’t use a 10x20 canopy tent for one person.
Camping tents are allowed.
No overnight camping at the Start/Finish line on Thursday night (November 6). Our team will be working through the night preparing for the race.
Do not leave food out on Thursday evening. It will be gone by Friday morning.
You may drive to the parking lot and unload on Thursday to set up your canopy tent.
Tent setup begins at 1 PM on Thursday.
Please take your tent and belongings with you when you leave on Saturday. Any leftover tents, tables, chairs, coolers, or other items will be removed on Saturday evening.
Clean up your trash and take it to the dumpster located in the back of the parking lot.
We would like to avoid having to create an official dog policy, so please use good judgment.
No dogs that bark constantly or show aggressive behavior.
If you bring a dog, it must:
Be on a leash at all times.
Remain inside your canopy tent.
Be cleaned up after — owners are responsible for picking up and disposing of all waste.
Runners are responsible for the behavior and conduct of their crew.
No drug use or smoking illegal substances.
Be respectful of your neighbors and other participants. Cheer on runners as they pass.
Place your tent directly next to your neighbor’s tent. If you leave a 5-foot gap, we will ask you to move it so there’s no space between tents.

For More Information

For more information join these pages:
Facebook Group: Mamba Trail Runners (this page is packed with information from group challenges to a runner's bio.)
Instagram: Mamba Trail Runners
Youtube: Mamba Trail Runners

Event's current local time: 7:09 PM CT