Dinosaur Valley Endurance Run

at Dinosaur Valley State Park

100 Mile / 100K / 50K / 25K / 5 Mile

NOVEMBER 23, 2019


Quick Links:      
Start Times Cutoffs Medical Awards
Location Drop Bags Crews Weather and Conditions
Parking Aid Stations Pacers Littering
Packet Pickup Aid Station Check-In and Dropping Out Timing  


Flooding last year caused us to switch to an alternate course. The alternate course was so popular last year that we will continue to use it in 2019!


Start Times

All races in 2019 start on Saturday, November 23.

100 Mile Saturday, November 23, 8:00 am
100K Saturday, November 23, 8:00 am
50K Saturday, November 23, 8:00 am
25K Saturday, November 23, 9:00 am
5 miler Saturday, November 23, 9:00 am



Get ready to run in Dino Valley! The race is held at the beautiful Dinosaur Valley State Park in Glen Rose, Texas. This course has rolling and sustained ascents and descents, although none are terribly steep. The loops take you through varied terrain, from double track trails in fields to single track in wooded areas. There is a mix of packed dirt, smaller rocks, larger rocks, slick rock, and some roots. There are also two river crossings per race loop. This course really has a little of everything, which includes its views. There are amazing overlooks on this course where you can see for miles.


To access parking, camping, AND the start/finish, use the following address: 4004 Co Rd 1007, Glen Rose, TX 76043. Since you can't always trust GPS / map software, please use these directions as you approach the area:

The back gate to the park is located five miles west of Glen Rose.

  • Take U.S. Highway 67 S through Glen Rose
  • Turn Right on to Hereford St/56 N (then go 4 Miles)
  • Turn Left onto CO RD 1007 (then go 2.7 Miles)
  • There will be a gate on your left.

Click on the map for a bigger version.

Parking is FREE. There will be a parking pass in your packet. Put it on your windshield if you will want to go over to the park's main gates before, during, or after the race and not have to pay entry over there. This is great for your family to enjoy the parks, your crew to access you at one of the aid stations, and you can use the park's restrooms and campground showers before and after the race!


Packet Pickup

What am I picking up? The following things will be in your packet:

  • Your bib (write medical concerns we should know about on the back as well as emergency contact numbers)
  • Safety pins. Pin your bib wherever you want as long as it's on the front of you AND my volunteers can clearly read it at each aid station. If you fold your bib, do not bend the foam chip on the back of the bib.
  • Your entrant shirt (we may not be able to swap sizes, but you can ask)
  • Your Parking Pass. Put it on your car windshield to get free access during the weekend at the State Park.

If you signed up in the couple weeks before the race, swag provided may be limited to whatever we have left.

Packet pickup will be in the times before each race starts. See the Schedule Page for times.

Please plan to arrive early so you have time to get your packet, run to the bathroom, and gear up for your race start, with enough extra time that you will NOT want to miss the trail briefing before we start.

Once your race distance starts, you have forfeited all rights to your packet, and the shirt in the packet will be made available to runners who showed up to the start of the race.



There will be no FINAL cutoff time (within reasonable limits - read on).

There are incremental cutoffs ONLY. You must make each of these cutoffs in order to continue in the race.

50K, 25K, and 5 Mile starting on Saturday means you have ALL DAY so enjoy your time out there without worries about cutoffs.

Here are the cutoffs for all distances. Note the mileages though are based on all distances BUT the half marathon.

Aid Station [ LAST LOOP ] Aid Station Split Cumulative Per Loop Last Time Thru Aid Station as Time of Day on SUNDAY for all distances Last Time Thru Aid Station in Elapsed Time for 100 Milers / 100K
Cedar Brake (S/F of loop)     10:45 AM 26:45
Fence Line (outbound) 3.1 3.1 2:00 PM 29:00
Fence Line (inbound) 4.3 7.4 3:00 PM 31:00
Cedar Brake 3.1 10.5 No Final Cutoff No Final Cutoff

For 5 Milers (or the first reduced loop for half marathon or 100 milers), you will hit Fence Line at mile 3.1 and then the Finish Line (Cedar Brake) at Mile 5.

These cutoffs represent the time you must be OUT of the aid station by. If a participant chooses to leave an aid station and return to the race course after the time cutoff or after being told by aid station volunteers that they are being pulled from the race, the participant is instantly disqualified and may be banned from future races.

If you leave an aid station before the cutoff but then backtrack and return to that same aid station after the cutoff, you will be pulled from the race.

The finish line will be stripped to bare bones at 3 pm but if you can make the final cutoff, we will wait for you with your buckle or medal at the finish, however long you take to make the final 3.1 mile journey, within reasonable limits (up to 3 hours for that final stretch).


Drop Bags

Participants can set out whatever they need at the start/finish area (Cedar Brake aid station).

No Drop Bags allowed at Fence Line aid station because of how remote it is to haul bags in and out.


Aid Stations

For each 10.5-mile loop of the course, below are the aid station details. See the Cutoffs section above for aid station cutoff details.

FENCE LINE is an aid station you hit outbound and inbound in the longer loop so make sure you know which way you're headed or ask the volunteers if you don't know. 5 milers only hit Fence Line once outbound.

CEDAR BRAKE is accessed at the start/finish of each loop. It is two-way traffic from Cedar Brake to Fence Line aid station.

Here's everything in one big chart:

10.5-mile loop:

Aid Station Aid Station Split Cumulative Per Loop Drop Bags? Pacer Changes? (starting mile 50) Crew Access? Portapotties or Bathroom Access?
Fence Line 3.1 3.1 NO NO NO NO
Fence Line 4.3 7.4 NO NO NO NO
Cedar Brake 3.1 10.5 Yes Yes Yes Yes

5 Mile (Reduced loop length):

Aid Station Aid Station Split Cumulative Per Loop Drop Bags? Pacer Changes? (starting mile 50) Crew Access? Portapotties or Bathroom Access?
Fence Line 3.1 3.1 NO NO NO NO
Finish 1.9 5.0 Yes NO Yes Yes

Aid Station details subject to change.


What We'll Be Stocking at the Aid Stations

WE ARE CUPLESS: We're a firm believer in the Leave No Trace principles of trail etiquette, so this will be a Cup-Free Event to eliminate the chance of litter. There will be no paper cups at this event. Everyone must carry some sort of hydration system with them, whether it's a handheld water bottle, a waist fuel belt, or a hydration pack. For other drink needs besides water at the aid stations, we recommend the Ultraspire C2 collapsible reusable cup or the Hydrapouch

WATER: Refreshing H2O at every aid station!

None of these foods or beverages below are guaranteed at any and all times. We'll stay stocked best we can. Choosing quantities to stock at an aid station is a total guessing game. If you want something certain, be sure to pack it in your drop bag.

The unmanned Cedar Brake aid station is only guaranteed to have water because you hit the Pavilion aid station only a quarter mile before.

ELECTROLYTE DRINK: The electrolyte drink on the course will be Tailwind Nutrition.

COLD FOODS: Most of the usuals at the minimum. Cookies, candy, peanut butter and jelly sandwiches, chips, pretzels, and more. Energy gels are such an individual item that we will not be providing - bring your own favorite if you want to use these as fuel.

HOT FOODS: At night, for the 100 milers, we will have hot food options of beef ramen and instant potatoes, maybe more options, and we will have coffee also.

Not all foods will be vegetarian friendly, and those with special needs (gluten-free or vegan, for example) and those who are super duper picky should plan to bring their own nutrition. Those with severe food allergies (like a nut allergy or celiac disease) need to be aware that we can not guarantee against cross-contamination.

Aid stations will not provide Advil, Aspirin, Motrin, or any other pain relievers.

Aid stations will not have blister kits. If you are concerned about blisters, carry what you will need in your pack or make sure it's in the drop bag at each location you might need to use it.


Aid Station Check-In, Check-Out, and Dropping Out of the Race

At every aid station, participants are expected to check OUT when leaving an aid station. If you are bib 482, when you arrive, yell "482 IN." When you leave, you or your pacer (for 100 milers) should yell "482 OUT" and check that someone is recording. This keeps our records accurate.

If you decide to drop out of the race, you must please let the aid station captain know and make sure they note it on their clipboard. We don't want you to leave with your crew and then we're calling you or your emergency contact a couple hours later looking for you, or searching the expanse of the trail system for you!

Volunteers will work to monitor every participant's ingress to and egress from the aid stations. We reserve the right to disqualify anyone whose times between any check-in or check-out do not grossly align with the paces expected based on their moving times the rest of the race and their racing history.



Each runner is responsible for their own actions. You need to be prepared both physically and mentally for all of the various stresses of the race. Our hope is to not have to call 911 for any of you. But in the event we have to in a medical emergency, medical expenses incurred are the responsibility of the participants receiving medical attention. Some parts of this trail are very remote to road access, and there may be a substantial amount of time that passes before medical personnel can arrive to provide aid.

Runners must understand all risks associated with undertaking this event. These physical and mental stresses include, but are not limited to, dehydration, hyponatremia, hypothermia, heat exhaustion, renal failure, seizures, hypoglycemia, disorientation, falls resulting in physical injury, complete physical and mental exhaustion, etc. Every participant is expected to monitor his or herself continually with an understanding of their own personal limitations. YOU, the individual participant, are absolutely responsible for your well being during and after the race.



Crews may access their runners at only the Cedar Brake aid station.

Crews may only access their runners within 200 yards of the aid station. Crewing a participant outside that area may result in disqualification.

Crews may not eat or drink from the aid stations (does not apply to pacers).

Failure by any crew member to follow the rules set out here may result in disqualification of their runner.



Participants can have a pacer starting at mile 50 (therefore, pacers are for 100K and 100 mile runners only).

Participants can pick up or change pacers at only some aid stations. See the aid station section above for details on each location. Participants can only be paced by one person at a time. Pacers and crews are responsible for getting the pacer shuttled back and forth to whatever aid station they are going to start from or end at.

Be sure to read the directions carefully on how to get to the Pavilion aid station, located in the Aid Station section above!

No pacers are allowed in the 50K, 25K, or 5 mile races.

No muling allowed. This means that a pacer may not carry or deliver anything to their runner unless within 100 yards of an aid station. This includes food and water. Muling may be lead to disqualification.

Pacers may eat and drink from each aid station just like the participants, but not until shortly before they start pacing. You don't get to nosh all Saturday when you won't start pacing until Sunday 2 am, for example.

Failure by any pacer to follow the rules set out here may result in disqualification of their runner.



The event will be chip timed. The "chip" is actually a tag attached to the back of the race bib. Unlike shoe chip tags, there are no special instructions for the bib tag.  They do not have to be looped a specific way, nor is there possible runner mishandling that can compromise RFID timing.  Do not take the foam cover off your bib chip. If you do not have a chip on the back of your bib, find the race timer by the start/finish early race day morning to get a new bib.

Some tips that enhance reader sensitivity, all of which are very standard practices:

  • Bibs need to be worn to ensure race timing.  If they do not wear a bib, they do not receive a time.
  • Bibs should be worn on the front of the body.
  • Bibs should be worn visible to anyone observing, so on the exterior of clothing.  If you wear a jacket and place the bib underneath, it can help if you expose the underlying bib upon mat-crossing to enhance reader sensitivity.  This is usually only a precaution.
  • Bibs should not be crumpled up and placed inside runner's clothing.

Failure to register on multiple timing mats or incredibly inconsistent timing splits between timing mats may result in investigation and potential disqualification. The same is true for those not registering in the written rosters of check-ins at aid stations or inconsistent or unreasonable splits from one aid station to another.

There may be at least one timing mat besides the one at the start/finish somewhere out on the race course. We will not be announcing the locations of all of these mats.

If you find you inadvertently go off course or take a wrong turn, you must return to where you left the course before continuing. If you cut a loop short and realize it, immediately notify volunteers to go find the race officials so a determination can be made as to how to help you complete the full distance.

Those not following the course will risk disqualification.


In each distance:
Top 3 Overall male and female
First place male and female in the following age groups: 00-29, 30-39, 40-49, 50-59, 60-99. If any distance grows substantially, we will consider going deeper in the awards categories.
There is no prize money.

Awards for The Active Joe races are small and will travel well in checked or carryon luggage.

Every finisher in the 5 mile, 25K, and 50K gets a finisher item. Every finisher in the 100K and 100 Mile gets a belt buckle (different buckle for each distance). Those who finish the 100 Mile in under 24 hours will receive a special "Under 24 Hours" buckle.


Weather and Conditions

Average low temperature is 53. Average high temperature is 74. But it’s Texas so the weather is known for being unpredictable. October is historically the rainiest month in fall.

Sunrise: 7:44 am. Sunset: 6:38 pm.

The weather can be unpredictable, but hey, that's Texas for you! The first year, 2014, was a mudfest of constant rain. This resulted in a 20% finish rate in the 100 miler, the 50 miler having to be canceled, and an unusually low finish rate for a 50K.

In 2015, 17 hours into the 100 miler, the entire race had to be cancelled. Storms came through Friday into Friday night, and what wasn't forecasted to happen, they just sat on top of us as we approached midnight. This led to significant flash flooding on the course, which has the highest point in Dallas but also has quite a few valleys and hollows. Runners reported chest deep water. We held the race for an hour to see if the storms would move through and when they didn't and we had more reports of bridges being out and snakes moving out on the trails in the higher elevations to escape drowning, we were forced to cancel all the events.

In 2016, we had a 0% chance of rain in the forecast, and it still managed to rain just about the whole event.

In 2017, we had record heat for DFW, with temperatures topping out in the high 80s.... in November.

In 2018, the weather was finally perfect!


No, just no. Don't. If we find you littering, you're disqualified. We are here by the permission of the property owners, and we want them to invite us to come back. Don't jeopardize that for everyone. If you get all the way out of the aid station with a gel wrapper, paper cup, or anything else, carry it with you to the next aid station.



All items above subject to potential significant change.


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