Event details subject to change. Please confirm all information via event website.
Boulder Peak Triathlon
Boulder Reservoir 5565 N 51st St, Boulder, CO, United StatesThe Boulder Peak Triathlon, Duathlon & Aquabike on July 10th is one of the countries longest and most well-known triathlons. For the veteran or first time racer, this is THE can’t miss event of the summer triathlon season, and the crown jewel of the Colorado Triathlon Series. Racers are tackling the infamous “Olde Stage” Hill, […]
Summer Splash Prairie Dog Half Marathon
Castle View High School 5254 N. Meadows Dr., Castle Rock, CO, United StatesWelcome to the Summer Splash Prairie Dog Half, 10k & 5k in Castle Rock, Colorado. Part of the Prairie Dog Half race series, join us in July as we race through Castle Rock along the East Plum Creek Trail.
Silverton Alpine Marathon
Memorial Park - Silverton 1800 Greene St, Silverton, CO, United StatesExperience the best of the San Juan Mountains with an 8 miler, a marathon, or a 50 kilometer run along the Alpine Loop past the historic mining ghost towns of Howardsville, Eureka, Animas Forks & Gladstone. High point is 12,930 ft atop California Pass. Low point is Silverton at 9,318ft. Total vertical gain is 3,800 […]
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 […]
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 […]
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