Ralston Creek Half-Marathon
& 5K Run

February 18, 2024
Arvada, Colorado

The Ralston Creek Half Marathon and 5K are back in 2024 and we are excited to announce the Racing Underground Winter Running Series also returns in 2024! Join us at Colorado's Premier Winter Half Marathon.

The Ralston Creek races feature a fun winter half-marathon and 5K run conveniently located on the west side of the Denver Metro Area in Arvada, Colorado. The courses covers a scenic mix of road and bike path over rolling terrain, and an optional early start time for half-marathon runners who expect to take more than 2.5 hours to complete the course!


HALF-MARATHON COURSE:The Ralston Creek Half Marathon course follows a mix of roads and bike paths on the west side of Arvada. The opening 5 miles are fairly flat, with a barely noticeable gradual gain in elevation. Miles 5 through 6.5 are rolling, with one good climb leading to the high-point of the course atop Ralston Mesa at 7.75 miles. From there, the course is almost all downhill and flat to the finish, with the exception of a small bump around mile 9 and a very gradual uphill in the last half-mile. Click Here for a Half-Marathon Course Map

Half-Marathon aid stations are located approximately every two miles throughout the course (approximate locations are: 2.25, 4.25, 6.5, 9.5, 11.5) All aid stations will have both water and Skratch energy drink. Hammer Gel will be available at miles 4.25 and 9.5.

5K COURSE:The Ralston Creek 5K Run course follows a mix of roads and bike paths on the west side of Arvada. The route starts with a slight downhill in the opening mile, a flat second mile, and a very gradual uphill in the final mile. A single aid station will be located at approximately halfway into the 5K run. Click Here for a 5K Course Map


Runners Roost Lakewood

The Ralston Creek Half Marathon serves as the final race in the Racing Underground winter running. The series has been extremely popular, selling out two of the three events every year!

The three-race series includes the Stocking Run 5K in December, the Yeti Chase 5K/10K in January, and the Ralston Creek Half-Marathon & 5K in February. Choose from the 5K-5K-5K series or the 5K-10K-Half Marathon Series, and save on your entry fees when you choose the Race Series option.


The Ralston Creek races have three start waves. Waves 1 & 2 are for the half marathon runners. Wave 3 is for 5k runners.

Start Procedure & Cutoff Times: Racing Underground utilizes a 2-wave start procedure for its half marathon distance events - the 'Official' start time, and an optional 'Early' start time for athletes who will take more than 2 hours and 45 minutes to complete the course.

The Official start time for the Ralston Creek Half Marathon is 9:45am. The optional Early Start time is 9:00am. All runners and walkers must complete the course by 1:30pm. This means early starters have 4 hours 30 minutes to complete the course, and 9:45am starters have 3:45 to finish. All official finishers, regardless of wave, will be listed in the official results and will receive a finisher medal.

Why do we do this? There are two reasons why we use this two wave start procedure. First, the early start allows our slower runners to enjoy a better finish line experience, with more spectators on hand to cheer them in. The second reason is for course logistics.

There are no requirements to enter the 9:45am start, except that you must finish faster than 3 hours 45 minutes. If you are a 3:30 half marathon runner and you would like to start in the 9:45am wave, then you are welcome to start in the 9:45am wave.

The 9:00 Early Start requires that you MUST take longer than 2 hours 30 minutes to complete the course. If there is even a small chance you will run faster than 2:30, then you should start in the 9:45am wave. Early starters who run faster than 2:30 will not appear in the race results.

A 2:30 half marathon time is roughly an 11-minute and 30 seconds per mile pace.

  • 7:30 a.m. - Packet Pick-Up Opens
  • 9:00 a.m. - Wave-1 Start (half-marathon runners expecting to be on the course longer than 2 hours 45 minutes)
  • 9:45 a.m. - Wave-2 Start (half-marathon runners expecting to take less than 2 hours 45 minutes)
  • 10:00 a.m. - Wave-3 Start (all 5K runners)
  • 10:45 a.m. - 5K Awards Presentation*
  • 11:30 - Half-Marathon Top-3 Overall Awards Presentation*
  • 1:30pm - Finish Line Cutoff

  • 5k Overall Awards will be based on GUN TIME. An awards presentation for our top overall 5k finishers will take place at 10:45am.

  • 5k Age-Group Awards will be based on NET TIME. They will be presented immediately following the presentation of awards to our top overall finishers.

  • Half Marathon Overall Awards will be based on GUN TIME. An awards presentation for our top overall Half Marathon finishers will take place at 11:30am.

  • Half-Marathon Age-Group Awards will be based on NET TIME. Following the presentation of awards to our top overall finishers, age group awards winners may stop by the awards tent to pick up their awards as category awards have been confirmed. The awards tent will receive updated awards lists throughout the morning.

*** The scheduled time for the awards presentation may be moved a bit depending on weather and number of athletes still on course

INFORMATION: Most questions are answered right here on the race website. If you have a question that isn't answered here, call Darrin or Jill at 303-642-7917, or shoot us an email at darrin@racingunderground.com



Half-Marathon entry is limited to the first 650 registrations. 5K registration is limited to the first 350 entries. Once a distance has filled, we cannot accept any additional entries for that distance.

Your entry fee includes entry into the race, a finisher's medal (for half-marathon runners who complete the course), FREE race photo downloads, fun music, a racer goody bag, hot cocoa and tasty post-race food, entry into our sponsor merchandise drawing, and if you are one of the speedy guys or gals up front in the half-marathon, you may take home a bit of cash!!!

A long sleeve gender specific tech shirt will be included with all adult entries. Youth 5k entries will include a short sleeve 50/50 t-shirt.

Click button to register
online for Ralston Creek
or the Entire Series!

ENTRY FEES: Ralston Creek 5k or Half

  • 5K Run
    • $30 through Nov. 25th
    • $35 from Nov. 26 - Jan. 15
    • $40 from Jan. 16 - Feb. 8
    • $45 from Feb. 9 - Feb. 17
    • Youth age 12 & under pay just $25 pre-reg. for the 5K
  • Half Marathon
    • $65 through November 25
    • $70 from Nov. 26 - Dec. 31
    • $75 from Jan. 1 - Jan. 27
    • $80 from Jan. 28 - Feb. 8
    • $85 from Feb. 9 - Feb. 17

    Refund and Cancellation Policy: We will make all efforts to hold the race, regardless of weather conditions, however we reserve the right to alter or shorten the course, or cancel the event in the case of extreme weather. We also acknowledge that changes in COVID restrictions may force the cancellation of the event. You may cancel your entry and receive a 75% credit (excluding online processing fees) until 30 days before the race. Credit will be good through 2024. Refunds will not be issued for any reason. Entries cannot be transferred or deferred fewer than 30 days before the race. If the race is cancelled, all in-person entrants will be moved into the virtual category for their distance and will receive a $10 credit which they may use for any Racing Underground owned event through 2024. .


    PACKET PICK-UP: We will be offering two packet pick-up options

    EARLY PACKET PICKUP will be held at
    Runners Roost Lakewood on Friday February 16th from noon until 6:30pm. Runners Roost will have some great deals during packet pickup, so come ready to shop!!! Friends or family members will be allowed to pick up for you at early packet pickup as long as they have a signed note from you allowing them to pick it up on your behalf.

    RACE MORNING PACKET PICKUP: You may also pick up your packet on race morning immediately adjacent to the finish line beginning at 7:30am. Race morning packet pickup will remain open until 9:45am.

    Your packet will include your official Ralston Creek bib number with timing chip attached and a race shirt.

    Your timing chip will be attached to the back of your bib number. You must wear your bib number VISIBLY on the FRONT in order to receive a finish time and place. If your bib number is under your clothing you may not receive a finish time. Also, please DO NOT FOLD OR CRUMPLE YOUR BIB NUMBER. If the attached timing chip is damaged, it will not work.

    DIRECTIONS: The Ralston Creek Half-Marathon is conveniently located on the Arvada's west side. From Highway 93 (between Golden and Boulder), turn east on the 64th Ave Parkway. Drive east on 64th for approximately 3.5 miles. As you pass the Arvada West shopping center (on your left) you will turn left onto Gardenia. Take Gardenia 2 blocks to W. 65th Way. The race staging area will be to your right. Parking will be to your left.

    ***For directions from your house, just click the "View Larger Map" link below the map to the right. Click "Directions" on the left side of the larger map page, and you can enter your home address for turn-by-turn directions.

    PARKING: Follow the directions above. Parking for the race will be in designated lots as well as on side streets and also in the shopping center lot just a few minute walk south an west of the start/finish line. The lot that we have used in previous years has been leased by a large church that has moved into the area, and we no longer have access to that lot. Please do not park in business lots that have been coned-off. We do not have permission to use these lots.

    View Larger Map


    We'll have plenty of hot cocoa and tasty post-race food at the finish line to warm you up and fill your belly, including hot breakfast burritos and Jill's famous home baked banana chocolate chip bread!

    The party will continue at the nearby Colorado Tap House located on Ralston Creek trail at 14982 W.69th Ave where you can show you race bib any time on race day and receive $2 off a beverage item of your choice. With 30 taps there are plenty of beer options, but also cider, seltzer, wine and cocktails. They serve coffee drinks, kombucha, CBD Cider, Tommyknocker N/A Beer, Root Beer and soft drinks. They serve small food items and the food truck of the day rolls up at noon!

    RESULTS: Race results will be posted on this website live during the race. Participants must wear their bib and timing chip visibly on the front and cross the timing mat at both the start and finish lines in order to receive an official time. Runners who start in the early start wave will be removed from the results and will not be eligible for awards or finisher medals if they run faster than 2 hours 30 minutes. Results will only be edited (for misspelled names, etc.) for two weeks following the event.

    2024 Results & Finisher Certificates
    2024 Race Photos (click your name in the results)

    2023 Results & Finisher Certificates
    2023 Race Photos (click your name in the results)

    2022 Results & Finisher Certificates
    2022 Race Photos (click your name in the results)

    2020 Results & Finisher Certificates

    2019 Results & Finisher Certificates

    2018 Results & Finisher Certificates

    2017 Results & Finisher Certificates

    2016 Results & Finisher Certificates

    2015 Results & Finisher Certificates

    2014 Results & Finisher Certificates

    2013 RESULTS

    2012 RESULTS

    AWARDS: The top-3 male and female finishers in the half-marathon will take home cash awards in the amount of $100, $75, and $50. The top-3 male and female 5K runners will receive merchandise or gift certificate awards. Overall winners will be determined by gun time (first three across the finish line are our top-3) and will excluded from age group awards.

    Awards will also be presented to the top-3 finishers in each age group in both the 5k and the half marathon. Age group placing is determined by net time (each runners time starts when they cross the start mat and ends with they cross the finish mat). 5k Age Groups are 12 & under, 13-19, then 5-year age groups from 20-24 through 85-89, and 90+. Half Marathon Age Groups are 19 & under, then 5-year age groups from 20-24 through 85-89, and 90+. We have also added a non-binary award category to the 5k and half marathon. The top-3 overall non-binary finishers in each distance will take home an award.