Colorado Triathlete

Bloch Ongert Beaver Creek Uphill & SkiMo
2026-01-11 | Beaver Creek, Beaver Creek, CO, United States
There’s Nothing Like First Tracks on Some Fresh Corduroy!
Come ski, board, or run with us until the sun comes up on some of the best ski slopes in Colorado! Kicking off the Winter Races is the Beaver Creek *Skimo/Boardmo and Uphill with over 2,000 feet of vertical gain from the base of Centennial Lift to Spruce Saddle Lodge. Get those thighs and quads burning as you earn your turns down Latigo. The event will conclude with breakfast and awards at Hawk’s Nest near the base of Beaver Creek.
Race will consist of skimo, boardmo, and uphill. Uphill can be done on skis, splitboard, snowshoes, spikes, or shoes with tred.

Snow Mountain Ranch Classic Race, GCNRS #2
2026-01-11 | Snow Mountain Ranch, 1101 Co Rd 53, Granby, CO, 80446, United States
Venue: Snow Mountain Ranch Nordic trails; Race HQ will be in the Camper’s Hub building
Event: Classic, Long Course 15km, Short Course 7.5km, Junior 3km
Course: Some long hills that will require pacing, fast descents and maybe a moose or two! The event will be based out of the new “campers hub building” adjacent to the Nordic center.
Start Time: 11am
Registration: Closes day of event

Grand Nordic 15K Skate Race, GCNRS #1
2026-01-10 | Snow Mountain Ranch, 1101 Co Rd 53, Granby, CO, 80446, United States
Venue: Snow Mountain Ranch Nordic trails; Race HQ will be in the Camper’s Hub building
Event: Skate, Long Course 15k, Short Course 7.5k, Junior 3k.
Course: Challenging 7.5 km loop that will test your early season fitness!
Start Time: 11am
Registration: Closes day of event

Vail Nordic Town Series Race
2025-12-23 | Vail Nordic Center, 1775 Sunburst Drive, Vail, CO, 81657, United States
The Vail Nordic Town Series Races are put on by the Ski & Snowboard Club Vail. Skiers of all ages and abilities are welcome to attend!
Day-of, on-site registration | $5 for 1K & 3K races, $10 for 5K and up

Peanuts 10km Skate
2025-12-13 | Crested Butte Nordic, 620 2nd Street, Crested Butte, 81224, United States
The Pinnacle Orthopedics Community Races with support by Salomon are a fun way to get outside, exercise, meet new people, and challenge yourself. Each week is a different format and location, with races ranging from 5 – 25km, plus a 3 – 6km short course option and a free 1 – 2km kids race.

Leftover Turkey 5km Classic
2025-11-30 | Crested Butte Nordic, 620 2nd Street, Crested Butte, 81224, United States

Last Call Triathlon
2025-09-28 | Boyd Lake State Park (Loveland), 3720 N County Road 11-C, Loveland, CO, 80538, United States
Yes! I want ONE MORE adventure!! Escape to the lake! The Last Call Triathlon will be an event you’ll look forward to all season long. Why? Beautiful mountain views, great weather and a family fun venue! Did we mention camping? Yup! There’s that too. Sitting on the east side of Loveland and southeast of Fort Collins, this close-to-home race day will have a family feel that’s intimate, fun and uniquely challenging. The course layouts make race morning packed with spectator cheering and multiple athlete flybys. With ON-SITE camping options, make a weekend out of this event and plan some extra relaxation time.

Oktoberfest Sprint Triathlon
2025-09-21 | Union Reservoir (Longmont), 461 County Road 26, 80504, United States
The Oktoberfest Sprint Triathlon features a half mile lake swim, a flat and fast single loop 12.9 mile bike, and finishes with a 3.1 mile run on a gravel road that hugs the lake. Please see course maps for a full description. Overall this is a beginner friendly course, and sets up very well for family and friends to spectate right alongside the action. The best part of Union Reservoir is how close the transition area, start line, finish line, expo area, and parking are to each other!

Desert's Edge Triathlon Series
2025-09-13 - 2025-09-14 | Highline Lake State Park, 1800 11.8 Road, Loma, CO, 81524, United States
Desert’s Edge Triathlon Series features two days of racing, including Sprint and Olympic distance road triathlons, and a sprint off-road triathlon for open and collegiate racers.

Littlefoot Triathlon
2025-09-06 | Bear Creek Lake Park (Lakewood), 15600 W. Morrison Road, Lakewood, CO, 80228, United States
Enjoy a fun late season tri at beautiful Bear Creek Lake Park in the Lakewood/Morrison area. Set at the base of the foothills, the Littlefoot Triathlon starts off with a 750 meter swim in Soda Lake, with water temps expected to be approximately 70 degrees. Next, a rolling bike 15K bike ride that covers nearly the entire park, offering great views throughout! Finish it up with a scenic 5K run on a bike path that winds through the park.

Boulder Sunset Triathlon
2025-08-23 | Boulder Reservoir, 5275 Reservoir Road, Boulder, CO, 80301, United States
Join us for an unforgettable morning at the Boulder Reservoir. Although this race does not take place at sunset, it will take place at the end of the summer– it’s sister race is the Boulder Sunrise in June. Experience gorgeous views at the recently upgraded venue. All participants receive stellar race shirts and finisher medals, too. This race is a favorite for beginners due to the flat bike course and a packed dirt trail run course.

Outdoor Divas Sprint Triathlon
2025-08-10 | Union Reservoir (Longmont), 461 County Road 26, 80504, United States
The Outdoor Divas Sprint Triathlon features a half mile lake swim, a flat and fast single loop 12.4 mile bike, and finishes with a 3.1 mile run on a gravel road that hugs the lake.

Stroke & Stride
2025-08-07, 2025-07-31, 2025-07-24, 2025-07-17, 2025-07-10, 2025-06-26, 2025-06-19, 2025-06-11 | Boulder Reservoir, 5275 Reservoir Road, Boulder, CO, 80301, United States
The 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 on 8 Thursday evenings (plus one Wednesday evening) throughout the summer. Many participants make their open-water swimming debut in the beginner-friendly Stroke & Stride 750 meter event, while more seasoned athletes get the thrill of starting alongside some of the top athletes in the world in the 1,500 meter swim. 250-400 participants enjoy the Stroke & Stride every week! Live timing, great post race food, beanie for 6-pack entries, and series prizes are just the beginning!

Stagecoach Gravel Triathlon
2025-08-03 | Stagecoach Reservoir (Steamboat Springs), 25500 County Road 14, Oak Creek, CO, 80467, United States
We 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 is set at Stagecoach Reservoir, a quiet and picturesque lake just 15min south of Steamboat Springs, with camping options for the entire family.
After the swim in the waters of Stagecoach Reservoir, it’s time to bring out either the gravel bike, road bike, or mountain bike. Just leave your triathlon bike at home. The course starts out with a short-paved section of 2.1 miles, before transitioning to rolling gravel country roads through some of the most scenic terrain imaginable. The total bike distance is 16 miles, with the final 3 miles of the course on pavement as athletes head back towards the transition area! Once off your bike of choice, it’s time to toss on those running shoes for a 4-mile run on a gravel trail that hugs the shoreline of Stagecoach Reservoir, (Note: ½ mile total on paved roads)! Come join us for this one of a kind triathlon experience, complete with a stand-up paddle-board option for the non-swimmers!

Boulder Rez Marathon
2025-08-02 | Boulder Reservoir, 5275 Reservoir Road, Boulder, CO, 80301, United States
This amazing run course will take you alongside the Boulder Reservoir, remaining mostly on dirt roads and trails. The course is flat with only 200 feet of gain, and will provide views of the Boulder Reservoir and Rocky Mountains.

Steamboat Lake Triathlon
2025-07-27 | Steamboat Lake State Park, 61105 County Road 129, Clark, CO, 80428, United States
After 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 to the most scenic bike course you’ll ever find. You’re more likely to see a herd of cattle crossing the road than be passed by a vehicle! After a ride through the rolling country-side athletes will transition to a 3.5 mile run course that’s 50% on road, and 50% on the dirt trails that hug the lakeside. When we tell athletes you’re running through wild flower meadows, we’re not exaggerating.
Pack the camping gear and make a weekend getaway for your all your friends and family! This year we’re also offering a aquabike, and stand-up paddle-board division!

Tri Boulder
2025-07-19 | Boulder Reservoir, 5275 Reservoir Road, Boulder, CO, 80301, United States
As one of Colorado’s most popular summer triathlons, Tri Boulder offers many different multisport race distances, all in one eventful day! Join us for a full day of racing at the Rez.

Boulder Peak Triathlon
2025-07-13 | Boulder Reservoir, 5275 Reservoir Road, Boulder, CO, 80301, United States
The 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, boasting an average 15% grade on their way to the finish line! This race has earned it’s spot on more than a couple notable “Best Triathlons in America” lists. In 2017, the Boulder Peak was listed as one of the top 15 most amazing triathlons in the United States by The Culture Trip!

LG Triathlon
2025-07-12 | Gypsum, Gypsum, CO, United States
Join us for the Annual LG Tri, a sprint triathlon in the beautiful Vail Valley town of Gypsum, Colorado. The course features a 500-yard open water swim, a 12-mile bike ride, and a 5K run. Adults can race as individuals or form a team. We’re also running the 12th annual Kids Tri, so bring the whole family! We’re excited to collaborate with the Siena Valley Club neighborhood — just a short drive from Eagle County Airport.

Boulder Sunrise Triathlon
2025-06-29 | Boulder Reservoir, 5275 Reservoir Road, Boulder, CO, 80301, United States
Kick off your summer of racing in Boulder.

Loveland Lake to Lake Triathlon
2025-06-21 | North Lake Park (Loveland), 2750 N. Taft Ave., Loveland, CO, United States
This event provides a beautiful venue. The transition area and lake are near North Lake Park. North Lake Park is a nice setting for competitors and families. It has a children’s train that operates throughout the day and is adjacent to Benson Sculpture Park, which is the site of Loveland’s annual Sculpture in the Park each August.

XTERRA Lory
2025-06-21 | Lory State Park (Fort Collins), 708 Lodgepole Drive, Bellvue, CO, 80512, United States
XTERRA Lory Triathlon on June 18th is the perfect kick-off to the year for the seasoned off-road triathlete, or a great opportunity for the road triathlete wanting to try out a mountain bike triathlon for the first time.
The XTERRA Lory Triathlon features a 1/2 mile swim in the clear waters of Horsetooth Reservoir (Eltuk Bay), it’s one of the most scenic swims in the state with canyon walls on both sides. Then it’s on to a 2-Lap (beginner friendly) 12.2 mile single-track bike over rolling terrain, and across valley bridges at Lory State Park. Then you’ll get to finish things off with a fun and challenging 4.8 mile (8k) run through the clouds on single-track trails! This is the perfect off-road triathlon for beginners to experts. The course is designed so that anyone can have fun and everyone will be challenged! Entries will be limited to 350 participants, and we sold out 2011-2021 in early April!
BACK FOR 2022: Stand Up Paddleboard Option instead of the 1/2 mile swim (you must bring your own SUP)!

IRONMAN 70.3 Boulder
2025-06-14 | Boulder Reservoir, 5275 Reservoir Road, Boulder, CO, 80301, United States
Presale Registration for 2023 IRONMAN 70.3 Boulder opens at 10am MT on Thursday, August 4, 2022.
