top of page


Half Marathon, Marathon, 100k, 100M




Event Description

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

The Brazos Bend course is the fastest trail in Texas trail running. The course is 99.9% flat, and the only hill is 10 feet. Other than that you will be running on flat surfaces that move from hard crushed rock, soft hiking trails under tree canopy, and easy horse trails. Conditions in the Spring are typically warm and humid but can still start with some cooler mornings. 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. Enjoy them on your run, from a distance, and you may get some unique race photos!

Western State Qualifier

The Brazos Bend 100 miler distance has been an official Western States Endurance Run qualifying race for over five years. Since BB100 is held in early December, around the same time as the WSER lottery, our race will earn you a raffle ticket to the following year's lottery for the next years WSER. Example: If you qualify in 2023 you will earn a 2024 raffle ticket for the 2025 WSER lottery. Official letter from WSER:

"We [WSER] are pleased to inform you that the 2023 Brazos Bend 100 has been selected as a qualifying race for the 2025 Western States 100. Runners who complete the race within 30 hours will qualify to enter a lottery where the runners for Western States will be selected. You do not need to submit anything to us, we will obtain the results directly from your website.


The qualifying period for the 2025 Western States will be from November 6, 2023 through November 3, 2024. The lottery will be held on December 7, 2024 and the race itself will be run on June 28-29, 2025."

WS100 2025 QUALIFYING RACE Western State 100 lottery ticket raffle ultra marathon entry easiest qualifier for western states fastest 100 miler brazos bend

Registration and Waitlist

Registration for the 2023 100M event opens on Friday, February 10th at Noon.


Registration for all other events will open on April 1st. New for 2023 we have replaced the 50M distance with a 100k event, and the marathon and half marathon have moved to Sunday. Stay tuned for more exciting additions to this weekend of events. 


This is a sell-out race, with entry numbers limited by the park. Sell-out happens earlier every year by about October.


New for 2023 we have opened a waitlist, as participants remove themselves from any event a new spot will be opened to the waitlist.


Do not wait to register, there is no other way to guarantee a spot!.

2023 Schedule

Saturday, December 2nd

100M : 6:00 AM
100k : 6:45 AM


Sunday, December 3rd

26.2M : 7:00 AM
13.1M : 7:45 AM

More details for 2023 coming soon...


Finish Line Closes (all races end): Sunday 3:00 PM

  • 33H 100MI

  • 32H 15M 100k

  • 8H Marathon

  • 7H 15M Half Marathon

Race Director will assess each runner leaving for their final loop and has the ultimate decision, along with the Medical Director and Park Staff, throughout the event for runners to continue.

Note that runners must be under 30H for WSER qualification.

Dropdown & Event Change

You may change your registered event during open registration on UltraSignup per the TROT policies.

Aid Station and Support

Brazos Bend 100 will have a total of four fully stocked aid stations on the course.

ALL runners must carry a form of hydration (bottle, flask, bladder, etc.) there will be NO cups at the aid stations.


  • Start/Finish Main Aid Station

  • 40 Acre 

  • Gravel Pit

  • Sawmill

Runners, family, friends, and crew are encouraged to set up their own hang-out support area around the large grass area at Elm Lake Pavillion for extended rest periods, personal gear, and preferences for food and hydration. It is common for clubs, teams, and families to have a tent (no camping) set up to enjoy the day. 

Aid Station Separation Distances for each loop (tentative):


Elm Lake Start to 40 Acre Aid: 3.05mi

40 Acre Aid to Gravel Pit Aid (after Hale Lake Loop): 5.64mi

Gravel Pit Aid to Sawmill Aid (after Yellowstone out-and-back): 3.6mi

Sawmill Aid back to Gravel Pit Aid: 3.23mi

Gravel Pit Aid back to Finish: 1.2mi

Aid Station Items (subject to change/while quantities last for non-critical items):

Fluids: Water, Ice, Gatorade, and Base Performance

Soda: Coke, Ginger Ale, Orange.

Electrolytes: Base Performance and Table Salt

Bars: Base Performance Bars

Sweet: Cookies, Candy, Peanut Butter, Nutella

Salty: Pringles, Trail Mix, Chips 

Food: Sandwiches (PB&J, Nutella, PB, etc), Bean burrito rolls, fruit (bananas and oranges)

Medical: Bandages, Vasoline, Band Aids (limited), etc. ( NO NSAIDS e.g. ibuprofen) , Feminine Care Products

Trail Toes at all aid stations with tape 

Cooking (evening only): Grilled Cheese, Quesadillas, Soup, Noodles, Coffee, Hot Chocolate, Ramen, Potatoes, and other "fun ultra concoctions".

Other: Cooling bucket, Gatoritas (hot weather), and other surprises!


We will have everything you need at our aid stations and usually throw in something extra at each event to make it fun. It's not uncommon to see cakes, pies, watermelons, etc… You never know what the surprise will be!

Aid stations are for registered runners only, during the event (not before). Serving is by our volunteers and staff only. Crew members are not to use aid station supplies. Runners and crew are encouraged to have their own supply, especially for particular items or certain diet requirements.

Drop Bags

You can have a drop bag at all of the aid stations for the 100k and 100 mile distances. 

There will be drop bag locations marked at the Elm Lake Pavilion starting Friday night. We will take them out to the course at 5:30am Saturday morning. 

We will return the drop bags around 1:30 pm Sunday as we break down the aid stations. You may have them shipped back to you (at your expense) post race. 

Pacers & Crew

100k runners may have a pacer for the final loop only.


100 milers may have a pacer for the final two loops only.

Pacers will register on UltraSignup the same way participants register, stay tuned for pacer registration opening in the Fall. 

There are NO pacers in the half marathon and marathon events. 

Crew is allowed at any aid station. All of them you will need to walk to or bike. You may access the Sawmill Aid Station via car which you will need to head out of the park go north and head east on sawmill road 3 miles. The aid station will be at the end on the right but there is no official parking so you will have to be on the side of the old road. 

Passes, Parking, and Camping

Every person 13 and over entering the park will require a special events state park pass for the weekend which includes park entry, trail use, and primitive camping. This fee goes directly to Brazos Bend State Park. Receipt of digital payment should be shown at packet pickup in exchange for wristbands for the weekend. You may pick up pre-purchased wristbands for others with a digital receipt. All passes are available on UltraSignup under the event store.


2023 designs coming soon...

Here are our designs from the 2022 event:

BB100 Shirt
BB100 Hoodie


2023 designs coming soon...

Buckles for 100M and 100k

Medals for Half Marathon and Marathon

BB100 Buckles


2023 updated info coming soon...

The course has remained mostly the same for years, below is our April event course map as an example which will follow very close for our December event. 

BB50 Map.jpg


2023 info coming soon...

School buses will shuttle between parking lots to Elm Lake Pavilion as we did very efficiently for BB50.


Earn future race credits, race swag, free park pass, food, and volunteer hours (as needed). Club support options are available as well for team aid station takeovers.

See more info on our volunteer page: VOLUNTEER WITH TROT


Altra Running Trail Ultra Marathon Shoe Best Shoes Run Footshape Cushion Lone Peak Torin Cal Neff
bottom of page