Dinosaur Valley Endurance Run

at Dinosaur Valley State Park

100 Mile / 100K / 50K / Half Marathon / 5 Mile



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  


We are forced to use Alternate Course B for 2018. Please see the Runners' Manual which overwrites whatever is on this page.


Start Times

All races in 2018 start on Saturday.

100 Mile Saturday, December 1, 8:00 am
100K Saturday, December 1, 8:00 am
50K Saturday, December 1, 8:00 am
Half Marathon Saturday, December 1, 9:00 am
5 miler Saturday, December 1, 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, Half Marathon, 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 3:30 PM 31:30
Unmanned Aid 5.0 12.4 No cutoff No cutoff
Pavilion (outbound) 1.0 13.4 4:30 PM 32:30
Pavilion (inbound) 2.9 16.4 No cutoff No cutoff
Cedar Brake 0.4 16.7 No Final Cutoff No Final Cutoff

Note that Daylight Saving Time ends Sunday morning at 2 am, so this is reflected above but you still get all the hours shown in the far right column.

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.

Since the pavilion aid station is only 0.4 miles from the finish line, that aid station will be torn down after 3:30 pm. The finish line will be stripped to bare bones at 5 pm so that we aren't doing all teardown in the dark. Thanks for your understanding.

If you can make the final cutoff and these conditions, we will wait for you with your buckle or medal at the finish, however long you take to make the final 3.3 mile journey, within reasonable limits (up to 3 hours for that final stretch).


Drop Bags

No drop bags for half marathon or 50K participants, except they can set out whatever they need at the start/finish area (Cedar Brake aid station).

Only one drop bag per aid station per participant please. Anything loose left on top of a drop bag will not be returned.

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

Gear Advice When Packing Your Drop Bag: Plan each of your drop bags appropriately with lights and spare batteries as needed.

There are two river crossings. Study the course map and decide when you want to have shoe or sock changes.

Bags will not be covered and will be exposed to the elements so plan accordingly.

Remember our aid stations do not have blister kits, so pack one anywhere you will need it. Review the aid station food and beverage lists and pack anything you require to fuel your body during the event.

For drop bags at Pavilion: Drop bags should be no bigger than a 2.5-gallon Ziploc bag or, for visualizing, the size of a standard shoebox in 3-D containers. No coolers. Please put any liquids inside a Ziploc bag within your drop bag as the bags will be somewhat tossed around and you don’t want any gear/apparel in your drop bag ruined.

For drop bags at Cedar Brake (start/finish): They can be bigger than the size dictated above for Pavilion, but exercise reason. The Race Director reserves the right to tell you that you are taking up too much real estate in the Drop Bag area.

Labeling and Drop Off: Bags should be labeled with your name, number, and aid station name. Those to go out to Pavilion aid station need to be dropped off by the start of your race.

Getting Your Bag Afterwards: You can drive to the Pavilion aid station to get those drop bags. And the Cedar Brake bags are right there at the finish line. Drop bags must be picked up by 4:00 pm Saturday at the finish. Drop bags will NOT be mailed. Anything remaining will be donated.


Aid Stations

For each 16.67-mile loop of the course, below are the aid station details. See the Cutoffs section above for aid station cutoff details.

FENCE LINE is a double-sided aid station. In the 16.67-mile loop, runners will hit it twice. Follow all signage.

UNMANNED is a simple water only aid station for those who need a little boost in the longer stretch between fence line and pavilion.

PAVILION is at the nice covered park paviion by the picnic area, and there are bathrooms 50 feet away. You reach this aid station after the first river crossing of each loop and just before the end of the loop.

CEDAR BRAKE is accessed at the start/finish of each loop. You hit this aid station a quarter mile after the second river crossing. Because you access the Pavilion aid station heading back to the finish of the loop just 0.4 miles earlier, view Cedar Brake as an unmanned aid station with minimal support but with access to your drop bag.

Here's everything in one big chart:

50K/100K/100 Mile (on 16.67-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
River Crossing - 12.3 miles into the loop
Unmanned 5.0 12.4 NO NO NO NO
Pavilion 1.0 13.4 Yes for 100K/100M Yes Yes Yes
Pavilion 2.9 16.3 Yes for 100K/100M Yes Yes Yes
River Crossing - 16.4 miles into the loop
Cedar Brake (unmanned) 0.4 16.7 Yes Yes Yes Yes

Half Marathon (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
Fence Line 0.7 3.8 NO NO NO NO
River Crossing - 8.7 miles into the loop
Unmanned 5.0 8.8 NO NO NO NO
Pavilion 1.0 9.8 NO NO Yes Yes
Pavilion 2.9 12.7 NO NO Yes Yes
River Crossing - 12.8 miles into the loop
Finish 0.4 13.1 Yes NO 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

The 5 Mile does not cross the river.

Aid Station details subject to change.

How to get to the Pavilion aid station:

Do NOT use your GPS to get you to the state park to access the Pavilion aid station! Follow the directions below.

Each runner's race packet will have a Parking Pass to put on the car windshield. This will allow FREE state park access before, during, and after the race, so pacers, family, spectators, and crew can use that to their benefit. But any other vehicle coming into the state park will need to pay the $7 per adult entrance fee.

Directions from the start/finish:

  • Turn right out of the gate leaving the start/finish area to get back on Co Rd 1007.
  • After 2.7 miles, turn right onto Hereford Street.
  • After 4.1 miles, turn right onto Hwy 67.
  • After just 0.8 miles, turn right onto FM 205 N.
  • Go 2.9 miles and then take Park Road 59 to your right (you'll see Dinosaur World across the street).
  • Stay on Park Road 59 0.7 miles to the park entrance.
  • After being waved into the park by park staff if in the runner's car or paying entry fees at Park Headquarters, drive to the stop sign and take a left.
  • You will pass a couple small parking lots on your left and then you will want to park in the parking lot to the left where the small restroom building and dumpsters are. The park pavilion is past all the individual picnic tables which are past the restroom building.

Click on the map to see a larger version.


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. No hot foods at Cedar Brake aid station (runners go by Pavilion aid station a half mile before finishing each loop at Cedar Brake).

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 some of the aid stations. See the aid station section above for details on each location. Since space is limited, we reserve the right to ask multiple crew members taking care of one runner to limit to one to two crew members at that location.

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

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, half marathon, 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, half marathon, 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.


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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All Rights Reserved.