Event details subject to change. Please confirm all information via event website.
Colfax Marathon
City Park - Denver 1700 N York St, Denver, CO, United StatesCome join over 21,000 runners from all over the world in the Mile High City! 2 Days, 8 Races means a distance for everyone! 26.2 Marathon through the stadium, fire station, downtown, Sloan’s Lake, Colfax Ave, 7 miles of water 13.1 Half Marathon through Denver Zoo, Denver Fire Station, downtown, Colorado Firefighter Calendar on course Urban 10 […]
North Fork Trail Race
BPIA Community Hall 18050 S. Buffalo Creek Road, Buffalo Creek, CO, United StatesThe North Fork 50 Mile/50K is 100% trails, mainly single track and some double track, starting and finishing along lovely Buffalo Creek, in the mountains about 50 miles southwest of Denver. This is a pure ultra, a very special and unique race, deliberately kept small so each runner gets personal attention. There are no non-ultra […]
Harvest Moon Triathlon
Boulder Reservoir 5565 N 51st St, Boulder, CO, United StatesEst. in 2000 this Colorado classic provides the veterans to beginners a challenging, affordable, and competitive race with a local flavor. Whether this is your first event of the season, or a tune-up for a summer long course triathlon, don't miss the Harvest Moon! The Aquabike portion is one of the fastest growing Aquabikes in […]
Boulder Stroke & Stride I
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 […]
Summits Trail Runs
Granby Ranch 1000 Village Rd, Granby, CO, United StatesThe Summits Trail Runs occur at Granby Ranch Resort in Colorado’s beautiful Rocky Mountains. These challenging trail races offer a variety of distances ranging from shorter runs to ultra distances, each course showcasing sweeping mountain vistas, dense forests, and rugged alpine terrain. Runners experience varying elevation gains that test endurance as the routes twist through […]
Colorado Triathlon
Boulder Reservoir 5565 N 51st St, Boulder, CO, United StatesThe Colorado Triathlon is where Colorado comes to race! The Colorado Triathlon - sprint & olympic distances, duathlon & aquabike options . To make this the "can't miss" event of the season, we'll also have athlete hoodie sweat shirts, and the best swag bag of the season. For us this race is about one person, […]
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 […]
Colorado 13er
Home Depot 1200 Dillon Road Louisville CO 80027, Louisville, CO, United StatesThe Colorado 13er is THE event where the best parts of trail running and road racing combine to create a truly enjoyable, kind-to-your-body, well-supported 13.1 race! Seasoned runners and first-timers alike appreciate the excellent communication from the 13er race crew who make this event accessible for athletes of all levels.
Flamingo Day 5K
Sloan's Lake Park 1700 Utica Street, Denver, CO, United StatesJoin us for a fun and festive day at Denver's Sloan's Lake Park.
The 80’s Run
Highland Heritage Park 9651 S Quebec St, Highlands Ranch, CO, United StatesTHE 80s Are back! Are you ready? Then grab your old Nikes, Leg Warmers and Parachute Pants or SHORT shorts!
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