Event details subject to change. Please confirm all information via event website.

  • Beware the Bear Trail Races

    Bear Creek Lake Park 15600 W Morrison Rd, Lakewood, CO, United States

    Run the original Bear Creek Lake Park trail race - the Beware the Bear Trail Races - on October 17th. This trail race consists of a 14.2K or a 5K. Or do them both with the double! There is also a kids 1K.

    $30
  • Race to Cure Sarcoma 5K

    Berkeley Lake Park 4601 W 46th Ave, Denver, CO, United States

    The Race to Cure Sarcoma (RTCS) is the premier run/walk series in the United States, focused on raising awareness, providing education, and research funds for sarcoma. Each year, the Sarcoma Foundation of America (SFA) hosts more than (20) RTCS events across the country. We provide a unique space in the sarcoma community where patients, survivors, their friends, […]

  • Trick or Trot 5K

    Apex Center 13150 W 72nd Ave, Arvada, CO, United States

    Join the Apex Park and Recreation District Foundation for the inaugural Trick or Trot 5K! Runners and walkers of all ages and abilities are all welcome to join us for this Halloween celebration. Dress in your Halloween best for a chance to win prizes for the costume contest. There will be a separate 1-mile Trick […]

  • Spooky Sprint 5K

    Carpenter Park 3498 E 112th Ave, Thornton, CO, United States

    Get ready to lace up your sneakers (or your costume!) for Almost Home’s first-ever Spooky Sprint 5K! Join us on Saturday, October 25, 2025 at Margaret Carpenter Park in Thornton for a morning full of fun, community spirit, and impact. Whether you’re running, walking, or choosing to “sleep in”, every registration helps Almost Home provide […]

  • YMCA Creepy Crawl 5K

    Palmer Lake Regional Park 199 County Line Road, Palmer Lake, CO, United States

    Our annual "spooky themed" race starts at the Palmer Lake Regional Recreation Area.  We head down the scenic Santa Fe Trail for a bit then turnaround and finish with a lap around Palmer Lake.  This is sure to be a fun day for everyone!  Our Kids Monster Dash Fun Run is for kids 12 and […]

  • Eerie Erie 5K/10K

    Erie United Methodist Church 604 Holbrook St, Erie, CO, United States

    The world-famous Eerie Erie is a Halloween-themed 5k and 10k race that runs through historic downtown Erie and takes advantage of our beautiful trail system that weaves along the Coal Creek open space areas. The 10k passes by scenic Pleasant Hill Cemetery with panoramic views and where friendly spirits can’t wait to visit this year’s […]

  • MonsterDASH

    Sloan's Lake Park 1700 Utica Street, Denver, CO, United States

    Colorado's Favorite Halloween Runs....Each year the Theme Changes!! 2025 brings...SCARY CLOWNS / Circus Theme! Our best theme yet. Saturday Race is in Denver at 9:30am... then Sunday is in Louisville at 3:00pm on trails. This festival on Sloan's Lake, brings scary music, tons of Blow Ups, Carnival Games and Scary Clowns. The 5k and 10k […]

    $35.00
  • Halloween Fun Run

    Clear Creek Middle School 320 Chicago Creek Rd, Idaho Springs, CO, United States

    This Halloween, join us for a spooky 5k or 1 mile loop through the Pioneer Cemetery in Idaho Springs!!  Try for a PR or take a leisurely stroll as you trick or treat with the ghouls in the graveyard. DON'T FORGET TO DRESS UP! Our Halloween costume contest gives you even more reason to rock […]

  • Quick Draw @ McGraw Trail Race

    McGraw Memorial Park 39 Wellington Lake Rd, Bailey, CO, United States

    Come one, come all! And join us in the "Quick Draw @ McGraw" 2 Mile Trail Run, organized and hosted by CRATES Colorado and benefitting McGraw Memorial Park. This challenging trail course located directly south of the Keystone Bridge located inside McGraw Park will give runners of all skill levels a true test of their […]

  • Grand Valley Brew Runs

    BOO Run 5K

    WestCo Brewing 905 Struthers Ave, Grand Junction, CO, United States

    Costume up and bring your family and friends, we will haunt the town on our 5k route along the river while taking in the beautiful fall colors followed by a big costume contest, seasonal brews, hot chocolate and fun fitness games. Website link: https://grandvalleybrewruns.com/kannah-creek-brewing-company/ FB event page: https://www.facebook.com/events/737334659137680

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