Event details subject to change. Please confirm all information via event website.
Sarcoma Strong 5K
Hi all! Please join us at Sloan's Lake Park in Denver on 8/8 for a 5K to raise awareness for cancer! Specifically, sarcomas, a group of cancers that affect tissues […]
Eat. Run. Adopt. 10K
Join us for Berthoud’s first-ever community-driven 10k! In partnership with Berthoud Pet Supply, this isn’t just a race—it’s a moving feast with a mission. A portion of race registration proceeds […]
Summer Sizzler 5K
Join us for the annual Summer Sizzler! Whether you are looking to run, walk or just enjoy the race SWAG this race is a sure thing for a great time […]
Rocky Mountain Tri-Fest
Rocky Mountain Tri-Fest is Colorado's newest Multisport event, catering to the whole family. With events for everyone from mom and dad looking to try their hand at a gravel triathlon, […]
Bullfrog Summer Surge
The Bullfrog Summer Surge is a community first race morning built around movement, connection, and summer fun. Set at Addenbrooke Park, there's something for every pace: a timed 5K for […]
Berkeley Circuit
Event Description Berkeley Circuit Race Schedule: 8:30- Free and Fun Kids Quarter Mile (no registration necessary, just show up to race!) 8:45- Community One Mile Run (all paces welcome- walkers, […]
Roxborough Ultras
Roxborough Ultras is a late-summer trail ultramarathon in Roxborough State Park, Colorado, offering a 50K and 50M on fully marked, all-trail courses. Both distances feature sustained climbing, technical sections, exposed […]
Westminster Trail Race
Wayne Carle Middle School 10020 100th Ave, Westminster, CO, United StatesAfter a special night edition last year, Westminster returns to its traditional daytime format in 2026 — bringing runners back to a classic morning on the trails at Standley Lake.Now […]
Mt Sneffels Half Marathon
The Mt. Sneffels Half-Marathon and Kids Fun Run began 25 years ago. In 2021, the 10 K was added. The Race is the foundation’s major fundraising event of the year. It […]
Boulder Rez Marathon
The Boulder Rez Marathon is quickly becoming a Boulder classic! This isn’t just another run around the lake. September temperatures will create the perfect race atmosphere. BBSC will offer a […]
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