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Jan

26

2025

Morrison, Colorado (United States of America) - "Yeti Chase 5k/10k Run". This race is conveniently located on the scenic west side of metro Denver. Bear Creek Lake Park is known for its diverse bird and waterfowl population as well as stunning views of the foothills. The 5k and 10k races wander its 2500 acres with a mostly flat course - the 10k throws in a few rolling hills. Race is limited to 1,000 entrants and offers prize money for the top finishers. The Yeti Chase is also the second event in the Racing Underground Winter Running Series with prize money for the top performers and age group awards in every age category. Pick one race, or do all three! Series participants can choose the 5k-5k-5k Series or the 5k-10k-Half Marathon Series. Bear Creek Lake State Park, 15600 West Morrison Road, Morrison, CO, 303-642-7917. www.runsignup.com/Race/CO/Morrison/YetiChase

Feb

16

2025

Arvada, Colorado (United States of America) - "Ralston Creek Half Marathon & 5k". The Ralston Creek Half Marathon and 5K follow a mix of roads and bike paths on the west side of Arvada. The 5K is mostly flat and fast, with a small rise in the final mile. The opening four miles of the half-marathon are fairly flat, with a barely noticeable gradual gain in elevation. Miles 4 and 6.5 are rolling, with one good climb leading to the high point of the course atop Ralston Mesa. From there, the course is almost all down hill and flat to the finish. Aid stations every two miles. Finisher's medals for all half Marathon finishers. Prize money offered. The Ralston Creek Half Marathon & 5K is also the final event in the Racing Underground Winter Running Series with $3400 in prize money for the top performers, and age group awards in every age category. Pick one race, or do all three! Series participants can choose the 5k-5k-5k Series or the 5k-10k-Half Marathon Series. Sartorious, 6452 Fig Street, Arvada, CO, 303-642-7917. www.racingunderground.com/RalstonCreekHalf

Feb

22

2025

Denver, Colorado (United States of America) - "Chilly Cheeks Winter Duathlon". The event starts with a 2.5M run with a 10M bike ride on paved roads and followed by another 2.5M run. The run covers a mix of road, paved bike path and well maintained dirt trails. Road bike and fat tire divisions are offered. New this year - a relay division. Post race hot food & drinks provided. Each entrant receives a pair of Chilly Cheeks Sweat Pants!!! Cherry Creek State Park, 4800 South Dayton Street, Denver, CO, 303-642-7917. www.runsignup.com/Race/CO/Englewood/ChillyCheeksDuathlon

Mar

16

2025

Windsor, Colorado (United States of America) - "Lucky Brew 5k, 10k and 15k Race". All participants will enjoy chip timing, race photos, Lucky Brew Socks, and a fantastic after-party featuring beverages, food, and an awards ceremony for top finishers. The race starts and finishes at Eastman Park, offering stunning views of Longs Peak as you run an out-and-back course along the Poudre River Trail. The event takes place on Saturday, March 16, 2025, with the Athlete Village opening at 8:00 AM, followed by race-day registration and packet pick-up from 8:00 to 9:00 AM. The 15K starts at 8:30 AM, the 10K at 9:00 AM, the 5K at 9:15 AM, and the Kids Fun Run runs from 10:00 to 10:30 AM. Post-race festivities, including brews, non-alcoholic drinks, food, awards, and fun, will be held from 9:30 AM to 12:00 PM. http://go.evvnt.com/2793150-0?pid=6562

Apr

13

2025

denv, Colorado (United States of America) - "Three Creeks Half Marathon". Travel on foot through some of the most beautiful parts of Cherry Creek State Park, with a total combined elevation gain of only 253 feet spread out over 13.1 miles as the course follows the banks of Cherry Creek, Windmill Creek, and Cottonwood Creek on a mix of road, paved running trail, and wide dirt trails. Live online results and athlete tracking will be available. with splits at 5k, the halfway point, and 10 miles. Cherry Creek State Park - 4800 South Dayton Street, Denver, CO 303-642-7917. www.runsignup.com/Race/CO/Englewood/ThreeCreeksHalf

Sep

28

2025

Boulder, Colorado (United States of America) - "Boulderthon: Boulder Marathon, Half Marathon, 10K, 5K". Colorado's Premier Fall Race Series: Run a 5k, 10k, Half, or Full, at the foothills of the Rockies, in the stunning running mecca of Boulder. Run the streets Olympians train on, then celebrate at our epic after-party downtown! Boulderthon is one of the top-rated marathons in the United States: Named #5 Best Half Marathon in the US by Active, as well as #1 Best in Colorado and #13 Most Beautiful Marathon in the World by HalfMarathons.Net, Boulderthon drew over 7,000 runners from all 50 States and 18 Countries in 2023, nearly tripling in registration, and selling out. Tucked into a picturesque valley below the iconic Flatirons, Boulder, Colorado sets the backdrop for the top-ranked, signature Boulder Marathon, Boulderthon. Boulder is a world-class destination offering 300 days of sunshine and endless recreation, shopping, dining, cultural and entertainment choices. It's no wonder National Geographic named Boulder the Happiest City in America. www.boulderthon.org

Oct

05

2025

Denver, Colorado (United States of America) - "Hot Chocolate Run - Denver". America's sweetest run is back for our most indulgent Hot Chocolate Run season yet in Denver on October 5, 2025! With 5K, 10K, and 15K distances and a post-run party that'll make you go cocoa crazy, you and your friends will experience the ultimate chocolate celebration! http://go.evvnt.com/2699029-0?pid=6562