Event details subject to change. Please confirm all information via event website.
Steamboat Lake Sprint Triathlon
Steamboat Lake State Park 61105 RCR 129, Clark, CO, United StatesAfter last summer this event instantly became a personal favorite for our staff, volunteers, and athletes - come find out why! We couldn't be more excited about this course, this lake, and the overall experience. The swim starts out in the surprisingly warm waters of Steamboat Lake (74 degrees average race temp), then athletes transition […]
Backcountry Marathon
Rio Grande Park Aspen, CO, United StatesUtilizing the beautiful trails that surround Aspen, and now offering three distances - 50K, marathon and heavy half-marathon, all of which run almost exclusively on dirt trails. For the first time in 2025, Aravaipa is introducing an ultra distance that will follow the marathon course and include an out and back to the McNamara Hut […]
Sheep Mountain Ultras
Town of Fairplay Beach Beech Rd, Fairplay, CO, United StatesMake no mistake, the elevation profile for The Sheep Mountain 50 mile and 50k are docile looking. However, the average elevation of over 10,500’ and copious amounts of aggressive terrain, will see you waddle away from this race in shock. Come ready my friends, this mountain throws everything it has at runners, challenging you from […]
Stagecoach Gravel Triathlon
Stagecoach Reservoir 25500 Co Rd 14, Oak Creek, CO, United StatesWe didn't get the chance to launch this race in 2020, but that didn't diminish our passion for this brand new style of triathlon! To say this race is “unique” would be an understatement! Limited to just 250 athletes, we're excited to announce the first ever gravel triathlon to the Colorado triathlon landscape! This event […]
Boulder Stroke & Stride IX
Boulder Reservoir 5565 N 51st St, Boulder, CO, United StatesThe Boulder Stroke & Stride offers Boulder area athletes a fun 1-lap 750 Meter Swim, or 2-Lap 1500 Meter swim in Boulder Reservoir, followed by a 5k run on the reservoir dam. Stroke & Stride happens weekly on Thursday nights throughout the Summer from June 4th to August 6th WITH THE EXCEPTION OF Thursday June […]
CMRA/RMRR 5K
deKoevend Park 6315 S. University Blvd., Centennial, CO, United StatesJoin us for the August Trophy Series race and picnic at deKoevend Park in Centennial. This year our friends with the Colorado Masters will be joining us again for a great race and a fun post-race picnic!! We will be providing soda, seltzer, and chips. We ask that you bring your own picnic fare. We […]
Rocky Mountain Tri-Fest
Boulder Reservoir 5565 N 51st St, Boulder, CO, United StatesRocky Mountain Tri-Fest is Colorado's newest Multisport event, catering to the whole family. With events for everyone from mom and dad looking to try their hand at a gravel triathlon, to children looking to do their first triathlon. The Sprint and Super Sprint gravel Tris are beginner friendly with the bike course on the gravel […]
HRCA Splash Mash Dash Kid’s Triathlon
Recreation Center at Northridge 8801 Broadway, Highlands Ranch, CO, United StatesThe Splash Mash Dash Kids Triathlon is the perfect for kiddos looking for a way to "TRI" the sport of triathlon or tune up their skills for a larger race. The race will offer kids a safe and fun environment for racing. To encourage participation and enjoyment for all, The Splash Mash Dash Kids Triathlon […]
Outdoor Divas Triathlon
Union Reservoir 461 County Road 26, Longmont, CO, United StatesThe Outdoor Divas Sprint Triathlon on August 21st, annually awarded best women's event in Colorado by Competitor Magazine, is the all women's triathlon you've been waiting for! We intentionally keep the race cap low at 600 women to create a fun, festive, yet intimate racing environment. Great goodie bags, one of our biggest expos of […]
Pioneer Prairie Dog Half Marathon
Westminster Promenade 10600 Westminster Blvd, Westminster, CO, United StatesGet out to enjoy the crisp autumn air at the Pioneer Prairie Dog Half & 5k/10k! We will be celebrating autumn at the Start/Finish line located at the beautiful Westminster Promenade Terrace. Each participant will receive a Gender Specific Tech Tee to commemorate the day and half marathoners will receive a Finisher Medal! Stick around […]
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