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The Mammoth - Glen Rose

Name: The Mammoth - Glen Rose
Start: 2026-10-10
End: 2026-10-11
Location: Glen Rose

Glen Rose, United States • 10-11 Oct 2026

The Mammoth - Glen Rose

The Mammoth is a multi-distance trail running event held at the High Hope Ranch and Retreat Center in Glen Rose, Texas. The race takes place across a one thousand acre ranch located in the scenic Hill Country. The course utilizes two distinct sections: a 3.5 mile loop and a 7 mile loop. These loops are combined to create a 10.5 mile lap for participants.

The event features several trail distances and a fun run:

100K Ultra Trail Run
50K Trail Run
25K Trail Run
10K Trail Run
5K Trail Run
1K Mighty Mammoth Fun Run

Participants have access to two aid stations situated approximately 3.5 miles apart. One station is located at the main lodge, which serves as the race hub, and the second is at the Matazamo ranch house. The event follows an enviro-friendly policy and requires runners to bring their own bottles.

On-site amenities include exclusive locations for tent camping and boondocking for an additional fee per person. The event takes place rain or shine on a private ranch with well-marked trails. All finishers receive a shirt and a medal, while those completing the 100K distance receive a finisher buckle. The event is USATF sanctioned, and as a result, pets are not permitted on the course. Visit the organization's website for the most recent information.

United States Texas Glen Rose

Race information

Website Registration

100 km

100k Ultra Trail Run

50 km

50k Trail Run

25 km

25k Trail Run

10 km

10k Trail Run

5 km

5k Trail Run

The Mighty Mammoth 1k Fun Run

Visit the organization's website for the most recent information.

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