Chilly Cheeks Duathlon Series
2023-02-25 | Hobie Park, 4800 S. Dayton St., Greenwood Village, CO, 80111, United States
Denver’s low key, low cost multisport winter series!!!
The Chilly Cheeks Winter Series is composed of three fun run-bike events at the Cherry Creek Reservoir. We provide a marked and marshaled course, fast & accurate chip timing, light refreshments, and some fun mid-winter competition in the heart of Denver.
When you enter the three race Duathlon Series or Run Series Option by December 17th you will get a pair of Chilly Cheeks Sweat Pants included with your entry! These are perfect for pulling on post-race or for lounging around the house.

Audi Power of Four Ski Mountaineering
2023-02-25 | Aspen Snowmass, Aspen-Snowmass, CO, United States
The Audi Power of Four Race Series is a premier endurance race series utilizing the unique and amazing terrain of each of the four Aspen Snowmass mountains. Each race is designed to test the limits and skills of both elite and recreational athletes.

Boulder Rez Half Marathon
2023-04-15 | Boulder Reservoir, 5275 Reservoir Road, Boulder, CO, 80301, United States
Half Marathon, 10K, 5K, Relay

IRONMAN Texas
2023-04-22 | The Woodlands, Texas, The Woodlands, TX, United States
IRONMAN Texas has been selected to host the IRONMAN Americas Championship for 2023.

Barkin' Dog Duathlon
2023-04-22 | Cherry Creek State Park, 4201 South Parker Road, Aurora, CO, 80014, United States
Participants can choose from the standard 5K Run, 34K Bike, 5K Run event or the short course which challenges participants with a 1.2 Mile Run, 11 Mile Bike, 5K Run.

Dash & Dine 5K
2023-05-02, 2023-05-09, 2023-05-16, 2023-05-23 | CO
The Dash & Dine 5k run, Boulder’s favorite spring tune-up run series at the beautiful Boulder Reservoir in Boulder, CO.

NOCO Half Marathon & 10K
2023-05-21 | Boyd Lake State Park (Loveland), 3720 N County Road 11-C, Loveland, CO, 80538, United States
Spring is the season of renewal and running. We hope you join us for a fun adventure that embodies the spirit of springtime at the beautiful Boyd Lake State Park!
Choose from the Half Marathon (13.1 mile) or 10K (6.2 mile) for your run adventure. This course is on smooth paved walkways with about three quarters of a mile being off road. Beautiful lake and wildlife views and fun post race festivities. Did we mention almost no elevation gain? This is one flat course making sure you’ll set a new PR or enjoy a fun steady-paced morning run race

IRONMAN Tulsa
2023-05-21 | Tulsa, Oklahoma, Tulsa, OK, United States
Steeped in southern charm and lush greenspace, 2023 Certified Piedmontese Beef IRONMAN Tulsa is your chance to become an IRONMAN. Swim the calm waters of Keystone Lake, dig deep on iconic Route 66 and feel the rush of the cheering spectators through downtown. This is your year: Unleash your inner spirit.

Ordinary Mortals Triathlon
2023-05-21 | Pueblo, 2200 Bonforte Blvd, Pueblo, CO, 81001, United States
Ordinary Mortals Triathlon (OMT) is a reverse order sprint distance (5 km run, 12.5-mile bike, 300-yard pool swim) triathlon for all us “Ordinary Mortals” – from the first time triathlete to more competitive triathletes on a fun and challenging course.
Bring the kids for the youth triathlon, Mini Mortals Triathlon, after the adult race. This is a family friendly event often attracting several families of two or three generations racing together the same day!

Stroke & Stride
2023-06-01, 2023-06-07, 2023-06-15, 2023-06-22, 2023-06-29, 2023-07-13, 2023-07-20 | 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!

Colorado Triathlon
2023-06-03 | Boulder Reservoir, 5275 Reservoir Road, Boulder, CO, 80301, United States
Colorado Sprint Triathlon: 750 meter swim, rolling and fast 17 mile bike, and finishes with a 3.1 mile run
Colorado Olympic Triathlon: 1500m swim, 23.5 mile bike, and a 10k run
Colorado Olympic Duathlon: 5k run, 23.5 mile bike, and a 10k run
Colorado Aquabike: Will feature a 1500 meter swim and a 24.8m bike

IRONMAN 70.3 Boulder
2023-06-10 | 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.

XTERRA Lory
2023-06-17 | 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)!

Loveland Lake to Lake Triathlon
2023-06-24 | 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.

Boulder Sunrise Triathlon
2023-06-25 | Boulder Reservoir, 5275 Reservoir Road, Boulder, CO, 80301, United States
Kick off your summer of racing in Boulder.

Timberview Trail Run
2023-07-01 | Lory State Park (Fort Collins), 708 Lodgepole Drive, Bellvue, CO, 80512, United States
Crisp morning air and a summer sunrise in Colorado. YES PLEASE! Join us on the foothills at Lory State Park for a fun & beautiful morning trail race.
This run race features three distances (a 10 mile, a 5 mile and a 5K) that are great for just about any level athlete at any age. Run on a beautiful & scenic course among the treetops with views of Horsetooth reservoir, Fort Collins & the foothills. Bring the kiddos too as the 5K route is very beginner friendly.

LG Triathlon
2023-07-08 | Gypsum, Gypsum, CO, United States
The LG Tri is a sprint triathlon honoring VVCF grant recipient Laura Genelin. The course features a 500-yard swim (10 laps), followed by a 12-mile bike ride and 5K run. Racers can go it alone or form a team. We’re also running the Kids Tri, so bring the whole family! It will be held in the beautiful Vail Valley town of Gypsum in the Siena at Brightwater Neighborhood.

Frisco Triathlon
2023-07-14 | Frisco Bay Marina, 267 Marina Road, Frisco, CO, 80443, United States
Are you looking for a new challenge this summer? Register for the 8th Annual Frisco Triathlon featuring stand-up-paddle boarding, mountain biking, and trail running. This twist on a triathlon is open to all ability levels and encourages athletes to take on a new multi-sport event. The Frisco Triathlon was named “Best Triathlon” in Elevation Outdoors Magazine’s reader poll, 2016 Best of the Rockies.
The Frisco Triathlon will be held on a Friday; with the volume of people we see at the Frisco Bay Marina on the weekends, we feel that we can provide the best racer experience, as well as provide a safe environment for other Marina guests by holding the race to a Friday.

Donor Dash 5K
2023-07-16 | Washington Park, Denver, S. Downing St. and E. Louisiana Ave., Denver, CO, 80210, United States

Boulder Peak Triathlon
2023-07-16 | 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!

Lonetree Sprint Triathlon
2023-07-22 | Lonetree Reservoir (Loveland), Lonetree Reservoir, Loveland, CO, United States
The inaugural Lone tree Sprint was a success and we’re happy to be continuing this event on July 23rd!
We LOVE this event, great mid-season race, open water swim and bike course with minimal traffic and a flat out and back run on asphalt and dirt.
With a slightly longer bike than your traditional Sprint, this event caters perfectly to those who enjoy spending time in the saddle, especially through our beautiful Colorado Foothills.
