10K races near Thornton

The HRCA Wildcat Mountain Trail Races offer 10-mile, 10K, and kids’ run options in Littleton, Colorado. The event begins at the Douglas County East/West trailhead near Rocky Heights Middle School. The 10-mile race starts first, followed by the 10K, with the kids’ race taking place later in the morning. The course uses the East/West Trail, leading into the HRCA Backcountry Wilderness Area and its Wildcat Mountain trail system. This is a local, in-person trail event, distinct from road races. The available distances accommodate adults seeking a longer trail run and families with children participating in a shorter race.

The Lafayette Music Fest 5K/10K is a run-or-walk race held alongside a live-music festival in Lafayette, Colorado. Participants can choose between a 5K and a 10K. Rock for the People, a 501(c)(3) nonprofit, organizes the event as part of its mission to foster a more inclusive local music community by providing free and low-cost rehearsal and recording access. Both courses utilize the Coal Creek Trail in Boulder County and are designed as out-and-back routes for simplicity. The 10K features four aid stations approximately 1 to 1.5 miles apart, offering salty and sweet snacks, water, and electrolyte drinks. The 5K includes two aid stations with drinks and a limited snack selection. Awards are presented to the top three female and male finishers in each age group, ranging from 10-20 to 70+. The finish area offers a festival atmosphere with donuts, live music performances, and opportunities to enjoy the musical aspect of the event.

The Spooky Sprint - Denver is a Halloween-themed road race held annually at Chatfield State Park in Littleton, southwest of Denver. As part of the Bodies Race Series, it offers a family-friendly setup with options for a 5K, 10K, half marathon, or an untimed 1 Mile. Younger children have their own untimed dash. The in-person races feature chip timing with live results and awards, and a virtual option allows participants to run independently while still receiving event merchandise. The race course is a road race within Chatfield State Park, with distances from a 1-mile family option to a half marathon. The expected attendance is in the hundreds, suggesting a focus on local runners, families, first-time racers, and those seeking Halloween-themed fun, rather than a large-scale urban event. Registration includes a custom bib, a designer shirt, and a finisher medal, along with complimentary participant photos and post-race treats. Children aged 10 and under can participate in the dash for free without merchandise. The 5K and 10K events provide reduced pricing for participants aged 12 and under.

Washington Park hosts the SKECHERS Hot Chocolate Run, a community event bringing a sweet occasion to the local pathways. We return for another Hot, inviting participants to embrace the spirit of this recurring gathering. Runners will navigate the park's routes, finishing with a hot chocolate reward at the finish line. This event offers a cheerful experience, combining a run with a treat and holiday cheer.

The Halloween Trick or Trot Run is a San Francisco running event with 5K, 10K, and half-marathon options, plus a 1-mile Family Fun Run. It is designed for runners seeking a holiday race over a standard road run, with post-run Halloween candy provided. Virtual 5K, 10K, and half-marathon entries are also available for those who prefer to complete the distance independently. Registration is organized into waves, and each wave closes upon reaching capacity, encouraging early sign-ups. Runners may select an Eco-Registration for the 5K, 10K, or half marathon to forgo the race shirt. The availability of short, long, family, virtual, and no-shirt choices offers greater flexibility than a single-distance Halloween fun run.

Turkey Trails Denver is an annual Thanksgiving-themed running event in Denver offering a half marathon, 10K, 5K, 1 mile, and a Kid’s Dash. It accommodates various participants: adults can select a longer timed race, families can opt for a shorter distance, and children 10 and under have their own untimed dash. The half marathon, 10K, and 5K are chip-timed with live results. The 1 mile and Kid’s Dash are untimed. Registrations include a custom bib, designer shirt, and medal. The Kid’s Dash includes a youth-sized shirt and medal. Children can also run the dash for free without swag. The 5K and 10K have youth pricing for ages 12 and under. The finish area provides free photos and treats. A virtual option allows participation remotely while still receiving event gear.

The Louisville Trail Race offers half marathon, 10K, and 5K distances on dirt trails near Louisville Community Park in Louisville, Colorado. It provides a Front Range trail running experience, allowing both experienced and newer trail runners to select a course suited to their abilities. The routes are predominantly flat and dirt, utilizing an out-and-back structure on trails surrounding the park. A challenging hill near the finish offers views of the Flatirons and Front Range mountains. This event, now in its second decade, maintains a family-friendly atmosphere with post-race activities encouraging participants to bring guests.

The Denver Veterans Day Run begins and ends in Denver's City Park, offering 5K and 10K run/walk choices and a virtual participation option. The Colorado Veterans Project organizes this Veterans Day event, welcoming runners, joggers, walkers, children, and dogs. The most demanding event is the 10K Rippetoe Ruck Challenge, requiring participants to carry a 25-pound ruck or backpack. The day includes more than just the races. The Rippetoe Rucksack Challenge pays tribute to Army Captain Russell Brian Rippetoe. The event raises money to support veterans, honoring their service and sacrifice. Following the run, City Park hosts a parade and festival featuring marching bands, floats, car and motorcycle clubs, military vehicles, historical reenactments, local vendors, children's activities, entertainment, and a beer garden.

The Turkey Trek is a Thanksgiving race series held at Long Lake Regional Park in Arvada, offering four distances: a 13.1-mile Half Turkey, the 10k Turkey Trek, the 5k Turkey Trot, and the un-timed 2k Turkey Toddle. The 5k begins at 8:30 AM MST, with the half marathon starting at 8:40, the 10k at 9:00, and the 2k at 9:10. This staggered start accommodates runners and walkers of various abilities throughout the morning. The course ascends to a summit at the 3-mile point, featuring the Egg Nog Chug Challenge where participants can drink 5 ounces of eggnog for a chance to win a new pair of shoes. Following the exposed upper section, the path crosses a ridge for a mile before descending the mesa's east side. The route then transitions to a flatter straightaway with hay bales for the Hay Bale Hop Challenge. This clockwise loop returns to the park, and approximately one kilometer from the finish line, racers encounter the Fill Your Pie Hole Challenge, involving pumpkin pie before the final push. Half marathon finishers are awarded a mug.

Run Denver 'Mile High City' 5K/10K/13.1 is a local Denver running event offering 5K, 10K, and half marathon distances, taking place in late November. It functions more like a supported group run than a large race: each wave is limited to approximately 15 to 20 participants, both runners and walkers are accepted, and timing chips are not used. The atmosphere is intentionally relaxed. Bibs are distributed on race day, participant gifts are mailed out, and organizers can record times by bib number upon request. Waves begin in the morning and are filled sequentially, with a waitlist or virtual run offered once capacity is reached. Participants receive a shirt, medal, and entry into a virtual runner community; the virtual option also includes text-based coaching support prior to the run.