The Mammoth 2026 - 100K / 50K / 25K / 10K / 5K and Mighty Mammoth 1K Fun Run

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. 
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RACE DAY SCHEDULE

• 100K  -  07:00am
•   50K  -  07:15am  
•   25K  -  07:30am
•   10K  -  07:45am
•    5K   -  08:00am
•    1K   -  10:00am
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​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 
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PACKET PICK-UP

• RACE DAY on site
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PARKING

• Price INCLUDES Entrance and Parking
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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.
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COURSE MAPS - Viewable HERE

Ready to test your limits? The The Mammoth 2026 - 100K / 50K / 25K / 10K / 5K and Mighty Mammoth 1K Fun Run brings a highly anticipated Ultra, 25K, 10K, 5K, 1K to Glen Rose on October 10, 2026. Expect a fantastic route right in the heart of Texas.