Sponsored by:

Have an event to List?
Whether a race, special group ride, training opportunity, or cycling-related community event, the 303 calendar showcases it all.  To have an event posted here please follow this link:  Event Policy Submission & Guidelines

60k/100k Encierro Velo

Elbert City Park Elbert, CO

Elbert   Ready to test your courage? Or just looking for a adrenaline rush at the start of a awesome ride? Then Encierro Velo gravel grinder is your spring event. It will wake you up from your winter slumber! 100Read More

90k/160k Pony Xpress Gravel

Trinidad CO

Trinidad   Come discover the challenge’s Pony Express riders faced in the 1860’s. These earliest American racers speed across remote, desolate regions of America. They had to combine speed, endurance, and mental toughness just to stay alive. While at theirRead More

High Plains Gravel Grinder


Elbert   Come enjoy the challenging gravel roads around Elbert Colorado featuring a variety of terrain from rollers to short steep climbs. Test yourself on long stretches of gravel with views of Pikes Peak, beautiful local ranches and pine forests.Read More

Santa’s Little Greenway Grinder

Fountain Creek Regional Trail Grinde Dr. and Trapper Ln, Fountain, CO

Fountain   In the spirit of the popular NCSC Underground Fondo, and in the giving spirit of Christmas, I gift to you the inaugural Santa's Little Greenway Grinder! This is an unofficiated, self-supported, completely free and Open-to-Anyone, Strava-timed race fromRead More

Fountain Roubaix

City Hall 116 S Main St, Fountain, CO

Fountain   Starting & finishing in downtown Fountain, CO, the Fountain-Roubaix is the first event on our inaugural Tour of Colorado Series.  Evoking it's namesake, the infamous Paris-Roubaix, the course has more than 40 miles of El Paso County, ColoradoRead More

Cinco de Grindo

Kettle & Spoke Brewery 2500 47th St #12, Boulder, CO

Boulder   100km-Climbing-Dirt-Gravel-Singletrack-Checkpoints-Lucha Libre ¡Dios Mio! Cinco de Grindo returns for a day on the backcountry roads and trails of Boulder County. Mas Informaciòn: giddyupboulder.blogspot.com

The Wellington-Roubaix

Old Colorado Brewing Company 8121 First St, Wellington, CO

Wellington   The second gravel grinder in the Series, the Wellington-Roubaix is an epic challenge through Northern Colorado and the beautiful Pawnee National Grasslands with 3000  ft of climbing and miles of dirt roads -  a true gravel grinder!  Read More

Victor Roubaix

Victor Victor, CO

Victor   The Victor-Roubaix is an epic gravel challenge in the heart of the Rockies with nearly 9000 ft of climbing and incredible views. Start and finish in downtown Victor! Event details and registration here   Series Events May 5Read More