Brazos Bend 100

December 6th, 2025

Sponsored by Altra Running

Western States 100 Lottery Qualifier (sub 32-hour 100-mile) with 119 qualifiers in 2024!

This is the December edition of our popular Brazos Bend races, with the marquee event being the 100-mile.

The Brazos Bend 100 is the largest trail race in Texas and one of the fastest trail races in the world on flat and smooth trails with incredible support from aid stations on a multi-loop course. The top 3 runners were under 16 hours in 2024. The course is 99.9% flat, and the only "hill" is a 10-foot rise over 0.1 of a mile. The rest of the ~16.7mi loop is flat surfaces that move from hard crushed rock, soft hiking trails under tree canopy, and smooth horse trails. Most runners will use a road shoe like the Altra Vanish Carbon 2, Torin 8, or Flow 2 but under wetter conditons a trail shoe may be a better choice. Conditions in December can have a mix of anything, but are typically great for running, genneraly between 40-70 degrees. Brazos Bend is a spectacular State Park located just South of Houston/Sugar Land and is most known for its abundance of birds and American Alligators, among other wildlife. The gators are a part of our race; there has never been an incident in the park's 50-year history. Enjoy them on your run, from a distance, and you may get some unique race photos!

Complete the 50K or 50M in April 2025, AND the 100K or 100M in December 2025 to earn the Brazos Bend Challenge Coin.

Cutoff Times: for ALL races, the finish line closes on Sunday at 2 PM (32h 100M, 31h 100k, 31.5h Marathon, 31h Half Marathon). Final lap starts will be assessed to meet the course time limit at the discretion of the race director and staff.

Information for the 2025 event is continuing to be updated as we get closer to event day. We do not expect any major changes, but stay tuned to your email for updates. The RunSignup page is your best place for event information. Please try our AI Chatbot to ask any questions you may have.