The Mammoth - 100K / 50K / 25K / 10K / 5K and Mighty Mammoth 1K Fun Run
About this race
Get ready for The Mammoth Race Glen Rose FALL migration. This multi-distance trail run welcomes families and runners of all skill levels. Enjoy the Hill Country that surrounds this stunning ONE THOUSAND acre ranch. We can't wait to see you out there!
The Mammoth - Glen Rose, TX is a multi-distance trail running event located on the trails High Hope Ranch and Eco-Retreat. Distances offered are 100K, 50K, 25K, 10K, 5K and The Mighty Mammoth 1K FUN RUN. There will be two sections of the course: a 3.5-mile loop and a 7-mile loop. Both loops combined equal a 10.5 mile lap. The event will run from 7 am on Saturday morning until 9 am on Sunday morning. The starting line and Main Race Hub will be the main lodge on the Ranch. There are two aid stations on course: the main lodge at the starting line, and Matazamo ranch house. Aid stations are approximately 3.5 miles apart.
RACE CATEGORIES:
- 100K - 26hr Cut-off time
- 50K
- 25K
- 10K
- 5K
- Mighty Mammoth 1K Fun Run - NON-CHIP TIMED EVENT.
RACE HIGHLIGHTS:
- Finisher Shirts and Medals
- Generous Cut Off times - Cut off time for 100K only!
- Finisher BUCKLES for 100K Ultra
- Scenic routes through pristine natural landscapes
- Well-marked trails and 'round the clock aid stations
- Exclusive sites for tent camping and boondocking (no hook-ups)
- Post-race celebration. Music, food and refreshments!
ADDITIONAL INFO:
- PETS ARE NOT ALLOWED. USATF sanctioned event policy does not allow for animals to participate in competitions.
- The Mammoth is an Enviro-Friendly Event - B.Y.O.B (Bring Your Own Bottle)
RAIN or SHINE. In the event of inclement weather that would threaten the safety of the racers, the event or courses may be altered or the event may be delayed or canceled.
RACE DAY SCHEDULE
- 100K - 07:00am
- 50K - 07:15am
- 25K - 07:30am
- 10K - 07:45am
- 5K - 08:00am
- 1K - 10:00am
CLASSIC SWAG
- All participants will receive a Mammoth Race OFFICIAL Race shirt and a Finisher's Medal.
- Finisher BUCKLES for 100K ULTRAS
AWARDS
- NO PLACE FINISHER AWARDS. BRAGGING RIGHTS ONLY
PACKET PICK-UP
- RACE DAY on site
PARKING
- Price INCLUDES Entrance and Parking
OVERNIGHT CAMPING
- $10 per PERSON. NOT included in registration. Max 6 people per site. PAYABLE AT THE GATE
REFUNDS/TRANSFERS
- Race Entry Fees are NON-REFUNDABLE, however TRANSFERS to another Person, Category or Mammoth Event are allowed.
COURSE MAPS - Viewable HERE
Pick your distance
Trail running
100K Ultra Trail Run
50K Trail Tun
25K Trail Run
10K Trail Run
5K Trail Run
PACER - 100K Ultra Trail Run
Running
The Mighty Mammoth 1K Fun Run
$25.00 REGISTRATION - YOUTH SHIRT SIZES ARE SOLD OUT. WE CANNOT GUARANTEE A SHIRT.
Typical race-day weather
Based on 1 year of Open-Meteo archive data for this event's race dates in Glen Rose, plus the 3 days either side.
The sun rises at 7:31 AM and sets at 7:04 PM local time (CDT) in Glen Rose on October 10, 2026 — 11h 33m of daylight.
Course
No course map published yet.
The organizer hasn't released a route for this event, and we don't publish guesses. If you're the organizer, send us a GPX file and we'll draw the profile.
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Other races near Glen Rose
Different organizers, within 40 miles, in the next three months
Step Up for Seniors 5K
Run, Run, Rudolph 5K
Mountain Lakes Mania 5K & 10K
The Hybrid Runner Foundation 5th Annual Turkey Trot 5K
Where this page comes from. Race details were last updated on . We re-check listings regularly and again in the week before race day.
- Entries, prices, waves and inclusions — the event's official registration page
- Temperature and humidity — Copernicus ERA5 reanalysis via Open-Meteo (CC BY 4.0)
- Elevation and terrain relief — Copernicus DEM GLO-90, ESA (CC BY 4.0)
- Comparisons and counts — Race Discovery calendar, 3 Glen Rose events
Spotted something wrong? Tell us and we'll fix it.