Multisport
Calendar

Sign up for our Periodic email
Guide to Races in Colorado

Featured Events

Winter Running Series
Winter 2017-2018


Chilly Cheeks Winter Duathlon Series
Winter 2017-2018


Superior Stocking Run
Dec. 17, 2017


Yeti Chase 5K/10K
Jan. 28, 2018


Ralston Creek Half Marathon & 5K
Feb. 18, 2018


Three Creeks Half Marathon
April 22, 2018

Barkin' Dog Duathlon
May 6, 2018


Mt. Evans Ascent
June 9, 2018


Evergreen Sprint Triathlon
July 22, 2018


Littlefoot Triathlon
Sept. 15, 2018


Winter Running Series
Winter 2017-2018


Chilly Cheeks Winter Duathlon Series
Winter 2017-2018


Superior Stocking Run
Dec. 17, 2017


Yeti Chase 5K/10K
Jan. 28, 2018


Ralston Creek Half Marathon & 5K
Feb. 18, 2018



March 2018

  • 3 - Moab Off-Road Duathlon - (8k Trail Run/13k Mtn Bike) - Klondike Bluffs Trails- Moab, Utah - 8:15 a.m.- 970-389-4838
  • 3 Steamboat Pentathlon, Downhill Ski/SS/XC Ski/Bike/Run, Steamboat Springs, Colorado, 970.879.4300

April 2018

  • 28 Pole, Pedal, Paddle (Back country ski/Bike/Kayak), Crested Butte Mountain Resort, Crested Butte to Gunnison, Colorado, 719.221.1710

May 2018

Racing Underground May 2018 Events

Date Event Location Website
6 Barkin' Dog Duathlon Cherry Creek State Park - Aurora, CO Website

Details: For 20 years, the Barkin' Dog Duathlon has served as the unofficial opening race to Colorado's multisport season! Consistently one of the largest duathlons in the western US, the race sells out every year. The Barkin' Dog offers something for everyone, with a $1,000 prize purse for the elites, gender-specific tech shirts, a catered post-race meal, awesome sponsor drawing and more. Choose from the standard 5K run, 30K bike, 5k run or the shorter 2K run, 15K bike, 5K run. Beginners are always welcome, and more than 1,000 first timers have made their debut in the Barkin' Dog Duathlon!

Other area May 2018 Events

  • 6 - Barkin' Dog Duathlon - (5K Run/30K Bike/5k Run or 2K Run/15K Bike/5K Run) - Cherry Creek State Park - Aurora, Colorado - 7:00 a.m.- 303.642.7917
  • 19 - Summer Open Triathlon - (0.5M Swim/12.4M Bike/3.1M Run) - Union Reservoir - Longmont, Colorado - 8:00 a.m.- 303.408.1195
  • 31 Boulder Stroke & Stride #1, (750m-1500m Swim/5k Run), Boulder Reservoir, Boulder, Colorado, 6:00 p.m., 303.408.1195

June 2018

  • 2 - Longmont Kids Triathlon - (various distances) - Centennial Pool- Longmont, Colorado - 7:45 a.m.- 303.651.8406
  • 2 - Colorado Triathlon - (750m Swim/17M Bike/5k Run) - Boulder Reservoir - Boulder, Colorado - 7:30 a.m.- 303.408.1195
  • 2 Fort Collins Kids Tri, various distances, ODea Core Knowledge Elementary, Fort Collins, Colorado, 9:00 a.m., 970.488.4450
  • 3 - Longmont Triathlon - (525Y Swim/12M Bike/5k Run) - Centennial Pool- Longmont, Colorado - 7:00 a.m.- 303.651.8406
  • 7 Boulder Stroke & Stride #2, (750m-1500m Swim/5k Run), Boulder Reservoir, Boulder, Colorado, 6:00 p.m., 303.408.1195
  • 9 TRR Colorado Biathlon, (1M Kayak/5k Run), Cherry Creek State Park, Denver, Colorado, 9:00 a.m., 703.532.6070
  • 10 Ironman Boulder Triathlon (2.6M Swim/112M Bike/26.2M Run), Boulder Reservoir, Boulder, Colorado, 813.868.5940
  • 14 Boulder Stroke & Stride #3, (750m-1500m Swim/5k Run), Boulder Reservoir, Boulder, Colorado, 6:00 p.m., 303.408.1195
  • 16 - XTERRA Lory Triathlon - (0.5M Swim/12.2M Bike/4.8M Run) - Lory State Park - Bellvue, Colorado - 7:50 a.m.- 303.408.1195
  • 21 Boulder Stroke & Stride #4, (750m-1500m Swim/5k Run), Boulder Reservoir, Boulder, Colorado, 6:00 p.m., 303.408.1195
  • 23 TriBella Womens Triathlon (0.5M Swim/10M Bike5k Run) (0.25M Swim/8M Bike/2M Run), Cherry Creek Reservoir, Denver, Colorado, 8:00 a.m., 303.408.1195
  • 23 Lake to Lake Triathlon (1.5k Swim/30M Bike/10k Run), High School, Loveland, Colorado, 6:30 a.m., 970.669.6372
  • 24 - Tri on the Plains - (750m Swim/14M Bike/5k Run) - North Sterling Reservoir - Sterling, Colorado - 7:30 a.m.- 970.580.1166
  • 24 Tri the Boat Triathlon, Sprint/Olympic/Long Course, Stage Coach State Park, Steamboat Springs, Colorado. 8:00 a.m., 941.961.7575
  • 24 South Suburban TRYathlon, various distances, Goodson Recreation Center, Centennial, Colorado, 6:30 a.m., 303.483.7029
  • 30 - Lookout Mountain Triathlon - (525m pool Swim/10M Bike/5k Run) - Mt Vernon Country Club - Golden, Colorado - 6:30 a.m.- 303.960.8129
  • 30 Boulder Stroke & Stride #5, (750m-1500m Swim/5k Run), Boulder Reservoir, Boulder, Colorado, 6:00 p.m., 303.408.1195

July 2018

Racing Underground July 2018 Events

Date Event Location Website
22 Evergreen Sprint Triathlon Evergreen Lakehouse in Evergreen, CO Website

Details: Triathlon returned to Evergreen in 2012, to the rave reviews of participants! Evergreen Lake is a spectacular venue, and this 750 meter swim, 12 mile bike, 5K run course features world class scenery and a great foothills course just 25 minutes from Denver. Come see why this race has gotten bigger every year!!!

Other area July 2018 Events

  • 4 Cortez Burst Triathlon & Kids Triathlon, (500Y Swim/11.5M Bike/5k Run), Parque De Vida Park, Cortez, Colorado, 7:00 a.m., 970.749.6180
  • 8 - Boulder Peak Triathlon - (1.5k Swim/42k Bike/10k Run) - Boulder Reservoir - Boulder, Colorado - 303.408.1195
  • 8 LG Triathlon & Kids Triathlon, (500m Swim/12M Bike/5k Run), Pool, Eagle, Colorado, 7:00 a.m., 970.328.9565
  • 12 Boulder Stroke & Stride #6, (750m-1500m Swim/5k Run), Boulder Reservoir, Boulder, Colorado, 6:00 p.m., 303.408.1195
  • 14 - San Rafael Classic Triathlon - (750m Swim/15.5M Bike/52.9M Run) (1M Swim/31M Bike/5.8M Run) - Huntington State Park- Huntington, Utah - 6:30 a.m.- 801-505-8481
  • 14 Frisco Triathlon (3k SUP/12k Mtn Bike/5k Run), Frisco Bay Marina, Frisco, Colorado, 9:00 a.m., 970.668.9133
  • 14 Pagosa Duathlon, (6M Run/14M Bike/5k Run), (3M Run/8M Bike), (1M Run/2M Bike), Monument Park Road, Pagosa Springs, Colorado, 7:30 a.m., 970.264.1129
  • 19 Boulder Stroke & Stride #7, (750m-1500m Swim/5k Run), Boulder Reservoir, Boulder, Colorado, 6:00 p.m., 303.408.1195
  • 21 XTERRA Beaver Creek, (1M Swim/15.5M Bike/5.75M Run), (0.5M Swim/9M Bike/3M Run), Nottingham Lake, Avon, Colorado, 9:00 a.m., 970.845.5293
  • 21 Kids TRYathlon, (various distances), Recreation Center, Parker, Colorado, 8:00 a.m., 303.841.4500
  • 22 - Evergreen Sprint Triathlon - (750m Swim/12M Bike/5k Run) - Evergreen Lake House - Evergreen, Colorado - 7:00 a.m.- 303.642.7917
  • 26 Boulder Stroke & Stride #8, (750m to 1500m Swim/5k Run), Boulder Reservoir, Boulder, Colorado, 6:00 p.m., 303.408.1195
  • 28 - XTERRA Indian Peaks Triathlon - (1000m time trial Swim/22k Mtn Bike/ 7k Trail Run) - Eldora Nordic Center- Nederland, Colorado - 9:30 a.m.- 303-960-8129
  • 28 South Suburban TRYathlon, various distances, Cook Creek Pool, Lone Tree, Colorado, 6:30 a.m., 303.483.7029
  • 28 Without Limits Open Water Swim, 1.2M/2.4M Swim, Rueter Hess Reservoir, Parker, Colorado, 7:00 a.m., 303.408.1195
  • 29 - Outdoor Divas Triathlon - (750m Swim/12.4M Bike/5k Run) - Union Reservoir- Longmont, Colorado - 8:00 a.m.- 303.408.1195

August 2018

Racing Underground August Events

Date Event Location Website
TBA My Way or the Tri Way TBA Website

Details: After losing our venue in 2016, My Way or the Tri Way returns in 2018 with an exciting new venue!!! The only race where you choose the order you swim, bike, and run. Don't like one of the sports - no problem - just skip the one you like the least! This race has sold out 8 years in a row, and we expect to sell out again in 2018. Details coming soon!!!

Other area August 2018 Events

  • 2 Boulder Stroke & Stride #9, (750m-1500m Swim/5k Run), Boulder Reservoir, Boulder, Colorado, 6:00 p.m., 303.408.1195
  • 4 - Dash For The Splash - (250m pool Swim/8M Bike/2M Run) - Bertrum OConnor Swimming Pool- Sidney, Nebraska - 7:00 a.m.- 308-254-5355
  • 4 XTERRA Aspen Valley (1200m Swim/12M Bike/3.1M Run), Private Property, Carbondale, Colorado, 10:00 a.m., 303.408.1195
  • 4 Ironman Boulder 70.3 (1.2M Swim/56M Bike/13.1M Run), Boulder Reservoir, Boulder, Colorado, 813.868.5940
  • 4 BEC Triathlon, (400m Swim/15k Bike/5k Run), Nottingham Lake, Avon, Colorado, 8:00 a.m., 888.325.5940
  • 4 HRCA Splash Mash Dash, (500Y Swim/10M Bike/3.5M Run), (1100Y Swim/20M Bike/6.2M Run), Center at Northridge, Highlands Ranch, Colorado, 6:00 a.m., 303.791.2500
  • 5 Durango Triathlon (500Y swim/13M Bike/5k Run), Community Recreation Center, Durango, Colorado, 8:00 a.m., 970.375.7317
  • 5 Tri for the Cure, (500m Swim/10M Bike/5k Run), Cherry Creek State Park, Denver, Colorado, 7:00 a.m., 303.430.2969
  • 11 - Splashland Kids Triathlon - (various distances) - Splashland Hot Springs- Alamosa, Colorado - 9:00 a.m.- 719.298.0662
  • 12 - Steamboat Catamount Sprint and Olympic Triathlon - (750m Swim/12.4M Bike/5k Run) (1500m Swim/24.8M Bike/10k Run) - Lake Catamount- Steamboat Springs, Colorado - 8:00 a.m.- 303.408.1195
  • 18 Tinman Triathlon (pool swim), Lamar Swimming Pool, Lamar, Colorado, 7:00 a.m., 719.336.4376
  • 19 Evergreen Kids Triathlon (various distances), Buchanan Park Recreation Center, Evergreen, Colorado, 9:00 a.m., 720.880.1000
  • 25 - So Long to Summer Sprint Triathlon - (750m pool Swim/10M Bike/5k Run) - Middle School, Glenrock, Wyoming - 7:00 a.m.- 307.689.4930

September 2018

Racing Underground September 2018 Events

Date Event Location Website
15 Littlefoot Triathlon Bear Creek Lake Park - Lakewood, CO Website

Details: The Littlefoot Triathlon features a 750 meter swim in Soda Lake, a 15K single loop bike ride through the scenic 2,500 acre park, and a beautiful 5K run course that finishes in the expo area at the Bear Creek Marina.


Other area September 2018 Events


October 2018

  • 6 PowerMan Colorado, (2.5k Run/15k Bike/2.5k Run), (5k Run/30k Bike/5k Run), (10k Run/60k Bike/10k Run), High School, Lyons, Colorado, 8:00 a.m., 810.394.1538
  • 13 Durango Double Run & Ride, (10.8M Run/17M Mtn Bike), Horse Gulch, Durango, Colorado, 8:45 a.m., 970.403.4846
  • 20 - Splashland Triathlon - (5k Run/10M Bike/400yd Swim) - Splashland - Alamosa, Colorado - 9:00 a.m.- 719.298.0662
This site created by Racing Underground
All Images and content copyright (c) 1995-2018