Endurance Races in Beautiful Places
[jtabs theme=”smoothness” size=”xxsmall”]Overview::

Boulder, CO
October 11-12, 2013

Racer Manual

Boulder Marathoners:
We were sorry to hear that there will be no road events in Boulder for the rest of the year, but completely understand that our city needs to use it’s resources where they are so desperately needed right now. We feel fortunate that our 24 Hours of Boulder event is completely held at the Boulder Reservoir and can continue. We’d like to give cancelled Boulder Marathon runners an opportunity to test their training. Pre-register in the 100k relay category and you’ll get a 50% discount on the race! Just choose how many 7 mile laps you’d like to complete and we’ll assign you to a team. Click on the registration tab and specify that you’d like to run on the “Boulder Marathon 100k Relay Team”. Let’s bring back some of the positive outdoors energy that Boulder thrives on!

Team Relay, Solo Challenges, 6 Hour Nighttime Fun Run, 50K, 100K and 100 mile Categories

Race under the sun and stars in the running Mecca of Boulder, Colorado. 24 Hours of Boulder is a series of endurance races that brings out the sense of adventure, stubborn determination and fun in every competitor! This thrilling format has been popular with bike races for years and is now available to runners!

24 Hours of Boulder is all-day and all-night. Runners can participate in a number of different distances or timed events. For racers, this will be one of the most memorable events of your life. For spectators and crew, it will be a weekend festival where you will witness athletes pushing themselves beyond their personal limits of endurance. Whether you’re assembling a dream team, or you’re a recreational runner, there is a category designed for you. You can choose to race as a Solo runner, or create a team of up to ten people, depending on the level of endurance you wish. If you’re looking for a team or a team looking for another runner, check out Team Connect. For timed races, each participant is required to complete at least one 7.14 mile lap, however, the team’s objective is to complete as many laps as possible within the given time frame.

This race is a fast flat course. The course is an even mix of pavement, dirt road and smooth single track with a stunning view of Boulder’s front range. And after each 7.14 mile lap, you’ll return to Base Camp, complete with lots of food choices and the tent city with easy access to your gear, team and crew.

Halloween Costume Contest!!!

Come race in your best Halloween costume and win a prize. Costumes will be voted on at the awards ceremony and a prize will be given to the crew member and runner with the best costume. Runners must complete at least one full lap in their costume while crew members are anyone out there to support a racer or team.



6 Hour Nighttime Fun Run Male/Female

50K Male/Female


Solo – Male/Female


100K Relay (up to 8 racers)

24 Hour:

Solo – Male/Female

Extreme Team (3-5 racers)

Open division (6-10 racers)

Boulder 100 Male/Female

Pre Race procedures
Each racer must check in at the Base Camp no later than 20 minutes prior to the start of the race unless management is notified beforehand. Team Captains are allowed to check-in for the entire team but are responsible to inform team members of course/procedure details. Teams will receive their batons at check-in.
Solo racers will not have to carry a baton.



Pacers are allowed for solo 24 Hour runners and 100 milers only. All pacers must check in at the registration table.


Each team must have a representative captain. The captain is responsible for all the teams actions and will be held responsible for any rule infractions and all communications with race officials.

Pre-race Meeting

Although everyone is welcome, the team captain and solo runners must attend the pre-race meeting.

Recording Laps

Racers must log-in on each lap at the Base Camp located at the Start/Finish area. The team baton must be passed from one racer to the other within site of the timing official. There will be a running clock, therefore the lap splits will run from lap-end time to lap-end time. It is the team’s responsibility to verify that each racer is logged-out correctly. Each racer must clearly state your number and wait until the race official acknowledges that your time and number are recorded. There will also be a number check at the aid station. Time will not be logged and baton transfers are not allowed at this checkpoint. It is important that you check in at the aid station or your lap will not count.

Team Requirements

Each team member must complete at least one lap.


Water and food may be supplied to any racer, by anyone, anywhere on the course. However, racers must stay well clear of the course when taking food or water. A strict Leave No Trace policy will be implemented. There will be an aid station with water, sports drink and energy gels halfway through the course.

Bib Number

Racers must display their race numbers at all times.

Local Laws

Federal, state and county laws and ordinances must be followed at all times.

Staying on course

While running a lap, racers must stay on the designated course. Any racer that goes off the designated course (i.e. shortcutting) will result in a disqualification of that racer and team.


Official protests can only be made by team captains and must be made directly to the Race Director.

Race Director

The race director has the final say in any ruling, including rulings made by the co-director.

Quiet Hours

Quiet hours at night, will be imposed from 7:00 p.m. Saturday until 7:00 a.m. Sunday. During this time, noise must be kept to a minimum but the fun will continue.

Night Running

Racers entering the course two hours before sunset on Saturday and up to one-half hour before sunrise on Sunday must carry a light source and it must be in good working order. Racing with lights out is permitted but all runners must have some sort of lighting affixed to the outside of their clothing while light is off (i.e. glow stick). The course will be marked with reflective tape. We suggest using a headlamp or a handheld light that can be raised to eye level for night time navigation in order to maximize the reflective tape.

Consecutive Laps

A team racer may run consecutive laps, but must log-out at Base Camp after his/her first lap in order to log-in for his/her second lap. If the racer does not do this, only one lap will be counted. Solo racers will do this every lap.


Batons must be handed off within sight of the timing table.

Substituting a team member

In order to substitute a runner, the new runner must fill out all appropriate paperwork. All late fees will apply. Substitutions/changes are eligible until two hours before the finish on Sunday.


All racers finishing the 100 mile race in 30 hours, the 100K (including teams) in 15 hours and the 50K in 8 hours will receive a finisher’s memento.

Racers must complete his/her lap by the posted finish time. No partial laps will be counted. For timed races each team’s final placing will be determined by the number of laps the team has completed and the order of finish times for the team’s last lap. For example, a team that has completed 20 laps with a finish time of 8:20 a.m. would beat a team that completed 20 laps, with a finish time of 8:30 a.m. A team that completed 21 laps, with a finish time of 9:00 a.m., would beat them both. The awards ceremony will begin approximately 20 minutes after the cut-off.

Solo 24 Hours racers will not be entered into the 100 mile standings.

All 100 milers finishing before the 24 hour mark will be included in the 24 Hour awards at 9:30. All others will be given their awards as they cross the finish line.

100 Mile, 100K, 50K, 24 Hour: Medals will be awarded for 1-3 place in both male and female categories in each of the following age categories:
Under 30
Over 50

Unforeseeable circumstances

In the case of unforeseeable circumstances due to weather or other extenuating circumstances that prevents the safe continuation the race, race officials may end the race at any given time. Results will be based on team’s placement at the time race officials determine. This rule will be implemented in the most extreme cases for the safety of runners or officials.



6:30-8:30 am – race day registration, packet pick-up

8:45 am – pre race meeting (mandatory for team captains)

9:00 am – race begins

5:00 pm – registration for Fun Run

6:00 pm – Fun Run starts

7:00 pm – pacers are allowed for solo runners


12:00 am – Fun Run finish (awards to follow) and 100K cut-off

5:30-6:30 am – race day registration for 50K

6:45 am- pre race meeting for 50K

7:00 am – start of 50K

9:00 am – last lap must be completed for 24 Hours

9:30 am – post race awards for 24 Hours and 100 milers finishing before 9:00 am.

3:00 pm – 100 mile and 50K cut-offs

We will provide hot food throughout the night at the Base Camp and Hammer Gel and Hammer Heed/water will be provided at aid stations.


Online registration for the Boulder 100 Mile and 50K, register for all other categories here or download a registration form

Cost per person :

Early Registration (until February 1st)

6 Hour Nighttime Fun Run – $65
50K – $85
100K Solo – $105
100K Duo – $95/person
100K Relay (up to 8 racers) – $85/person
24 Hour Solo – $120
24 Hour Extreme Team (3-5)- $100/person
24 Hour Open division (6-10)- $90/person
100 mile – $165

Standard Registration

6 Hour Nighttime Fun Run – $75
50K – $95
100K Solo – $115
100K Duo – $105/person
100K Relay – $95
24 Hour Solo – $130
24 Hour Extreme Team (3-5)- $110/person
24 Hour Open division (6-10)- $100/person
100 mile – $195

Race Weekend Registration

6 Hour Nighttime Fun Run – $95
50K – $105
100K Solo – $135
100K Duo – $125/person
100K Relay – $115
24 Hour Solo – $150
24 Hour Extreme Team (3-5)- $130/person
24 Hour Open division (6-10)- $120/person
100 mile – $210

(deduct $10 per person for multiple race discount)

Media Discount

Racer Manual


2013 Results

2012 Results

2011 Results

2010 Results

2009 Results

2007 Results

2006 Results

2005 Results

2004 Results


Directions from Denver

  • I-25 N / US-87 N
  • Merge onto US-36 W via EXIT 217 on the LEFT toward WESTMINSTER / BOULDER. 18.1 miles
  • Merge onto FOOTHILLS PKWY / CO-157 N toward C U STADIUM. 4.9 miles
  • FOOTHILLS PKWY / CO-157 N becomes CO-119 N / DIAGONAL HWY. .2 miles
  • Turn right on N. 51st Street 1.1 miles
  • Turn Right in the Boulder Reservoir past gate/entrance to Main Beach parking lot. Registration will be at the beach house.

This race is run on the beautiful trails at the Boulder Reservoir with great views of the snow covered peaks. The course is a flat 7.14 miles (lap 14 ends at exactly 100 miles) with approximately 100 feet gain per lap with an aid station at approximately 3.5 miles. There will be apprximately 1,400′ for the 100 mile category, 840′ for the 100K and 420′ for the 50K. The course will be marked and is an even mix of pavement, two wheel drive dirt road and non-technical singletrack (so don’t worry about those late night hours).

View map of course:


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