Event details subject to change. Please confirm all information via event website.
Tri Boulder
Boulder Reservoir 5565 N 51st St, Boulder, CO, United States‘The Beast’ Long Course distance will be back for its second year! As one of Colorado’s most popular summer triathlons, Tri Boulder offers many different multisport race distances, all in one eventful day. Take in the natural beauty of the mountain backdrop that sets the scene for this iconic race destination. Most of the bike […]
Kendall Mountain Run
Memorial Park - Silverton 1800 Greene St, Silverton, CO, United StatesMeet the mountain this summer in Silverton, Colorado! The Kendall Mountain Run starts in downtown Silverton and traverses jeep roads to within a final 300 vertical foot scramble to the summit of Kendall Mountain overlooking town and the majestic San Juan Mountains. Ascend from 9,318 feet to 13,066 feet to tag the summit! Experience the […]
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 […]
PPRR Nielson Challenge
North Monument Valley Park 1794 Culebra Ave., Colorado Springs, CO, United StatesRace Format The first time you run this event, you'll establish a base time for yourself. This base time is used to generate a handicap time. The handicap time is calculated using an algorithm developed by Bob Royse, and it's geared to favor a beginning runner and the slower runners. Click here for an explanation of the […]
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 enters its 24th season in 2025, and 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 on 8 Thursday evenings (plus one Wednesday evening) throughout the summer. Many participants make their open-water […]
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 […]
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 […]
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