Event details subject to change. Please confirm all information via event website.
Resolution Run 5K
Ring in the New Year Durango-style! Lace up, layer up, and join the Resolution Run 5K for a refreshing start to 2026. This family- and pet-friendly event is perfect for […]
RMRR Platte River Trailhead Park 5K/10K
Platte River Trailhead Park Colorado Blvd and E 88th Ave, Thornton, CO, United StatesEveryone – slow, fast, or in-between – can win at RMRR Trophy Series races. With our handicap scoring system, we predict YOUR finish time based on recent running results, giving you a great […]
COPS 5K
Colorado State Patrol Track 2054 Quaker Street, Golden, CO, United StatesThe Colorado Outdoor Pace Series ("C.O.P.S.") is a unique set of races presented by Golden Mountain Runners and Golden Endurance. Race Dates January 7, 2026 - 5K January 21, 2026 […]
All-Out Polar Prowl
From the heart of the West Metro area and the Stenger Soccer Complex, All-Out brings you Polar Prowl! Along with its Endless Series sidekick in June… Summer Breeze, these 5K, 10K and Half […]
Sentinel Flurry 5K
The Sentinel Flurry returns for the 2025-2026 School year! It will take place on January 10th, 2026. Participants can sign up for the 1 mile, 5K or the Combo. Combo […]
PPRR Winter Series I
Red Leg Brewing Company 4630 Forge Rd, Suite B, Colorado Springs, CO, United StatesThe series consists of four progressively longer (LONG AND SHORT) races. Please note: You must choose your distance when registering. The Long Race starts at 10:00AM. Short Race starts at 10:20AM. The […]
CMRA Frozen Platte 8K
The course will go north from there on the S. Platte trail, across the suspension bridge at the Big Dry Creek Trail, back south on the west side of the […]
Beaver Creek Uphill
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 […]
Canceled Frosty’s Frozen Half Marathon, 10K and 5K
Frosty's Frozen Five & Ten is a flat and fast half marathon, 10K and 5K held each January in Littleton Colorado. The race starts and finishes at Hudson Gardens and […]
Trail Apples 4 Mile
We host one race per month from November to March. All races are at Chatfield State Park and start at 9:00 am on Saturday mornings. Check-in starts at 8:15 am.
Almageddon Winter Triathlon
Take on the ultimate winter endurance challenge at 10,653 feet in Alma, Colorado, the highest incorporated town in North America. The ALMAGEDDON Winter Triathlon combines fat biking, Nordic skiing, and […]
Colorado Cold Rush 5K/10K
Baby, it's cold outside... And we're gonna take it on, because that's what living in Colorado is all about. Let's conquer the elements together at this WINTERY January 5k/10k race. […]
Polar Bear 5K
The RunDenver Series is the original running series in Colorado and has been a staple for over three decades. Produced by HAL Sports, the series promises a fun time through […]
Chilly Willy Half Marathon
It's winter time & it's cold, but don't hibernate! Keep moving because it's a great time to go for a run whether you join us live or run virtual! We're […]
Rio Frio 5K
The Annual Rio Frio 5K on Ice is one of America’s most unique 5k races! This spectacular event is conducted entirely on the majestic frozen Rio Grande! Have you ever run on a frozen river? Come and try it out on January 29th in Alamosa.
Arrowhead Uphill
We traversed across Beaver Creek and into Arrowhead for the second installment of the VRD Winter Races! Participants can choose between *skimo/boardmo and uphill with approximately 1,700 feet of vertical gain […]
Canceled Chilly Willy Half Marathon
It's winter time & it's cold, but don't hibernate! Keep moving because it's a great time to go for a run whether you join us live or run virtual! We're […]
Freakin Freezin 5K
It's that time of year when brave runners lace up, layer up, and take on the chill! The Freakin' Freezin' 5K is all about starting the new year with some […]
Arches Ultra
Arches Ultra travels along the border of Arches National Park, using Bar M, Klonzo, and Klondike Trail Systems. The trails are smooth and easy at points, technical slick rock at […]
Sourdough Snowshoe Race
The race is intended to be a difficult and fun free of charge backcountry event; any and all plans can change due to trail conditions for the runner’s safety. Snowshoes […]
Old Man Winter Rally 5K/10K
Bundle up and get ready to run and/or ride Colorado's best mixed terrain at the Old Man Winter Rally in Lyons on February 6th. Runners can crush the 10K course of single track trails, red rock canyon and gravel paths while riders can choose a 50K or 100K of dirt, snow, climbs and thrills! With a ragin' after party with hot food and cold beer, what more could you want?
Running Up for Air
Running Up for Air unites our community over a shared passion for running and a desire to drive real, lasting change in the fight for cleaner air. Through endurance events […]
Westy Winter Waggle
Westminster Promenade 10600 Westminster Blvd, Westminster, CO, United StatesIt's the Westy Winter Waggle 5&10k! Come waggle with us along an accurately measured, professionally timed course where you're welcomed by super friendly volunteers who wanna waggle with ya in […]
Sweet Heart Run
This February, run your heart out, sweetheart! Choose between a 5K or 10K along the scenic Fruita Trail System, and don’t forget to dress up for the costume contest. After […]
Vail Mountain Winter Uphill
Join us as skiers, snowboarders and winter runners tackle 2,200 vertical feet of groomed trails to reach Eagle's Nest at the top of the Eagle Bahn Gondola in Lionshead. The […]
Super Sunday Fun Run
Reynolds Landing 6745 S. Santa Fe Drive, Littleton, CO, United StatesBring the entire family to run or walk before the big game and enjoy a post-race party at Breckenridge Brewery Farmhouse. Runners and walkers of all ages and abilities are […]
Toyota Super Half Mararthon
The streets and trails of downtown Colorado Springs are not exactly the “Frozen Tundra of Lambeau Field” but on Super Bowl Sunday, Feb.8, 2026, more than 1,500 runners will race […]
City LAX Dash
The Dash is an event to kick-off the spring season and support Denver City Lax. Schools, teams and individuals have been rallying together at the Dash the past nine years.
Valentine Twosome
This is just a fun, casual race with optional costumes. Grab your sweetheart, a friend or family member, just bring someone besides yourself, dress up in red, pink, any fun […]
Sweetheart Classic
Sweetheart City Racing is excited to once again hold this year’s event. With a race start and awards in Downtown Loveland it will be right in the center of the […]
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