Colorado · October
October Races in Colorado
Find races in Colorado taking place in October. Compare dates, locations, distances and registration information. Explore 20 race with a confirmed dates.
- Upcoming, date confirmed
- 20
- Active listings
- 70
Nearby months
Browse Colorado races by distance
Races in nearby states
Guides from the RaceRove blog
- 8 min read How to Choose the Best Half Marathon for a PR, Racecation or 50-State Challenge The best half marathon depends on what you want from it. How to choose a course for a personal record, a race worth travelling for, or an efficient stop on a 50-state challenge.
- 4 min read Diplo's Run Club 2026-27: Every City, Date and Course Diplo's Run Club is a 5K with a post-race concert. Every US date for 2026-27 (San Francisco, New York, Los Angeles, San Diego and Phoenix), start times and courses.
- 8 min read How to Choose Your First Marathon A practical checklist for choosing a first marathon based on course, weather, cutoff, travel, field size and support.
- Blog All guides Planning advice for finding, choosing and travelling to races.
October Races in Colorado: common questions
- How many races are there in Colorado in October?
- RaceRove currently lists 20 upcoming races in Colorado in October with a confirmed date, plus 50 annual events usually held that month whose next date hasn't been announced yet.
- What is the biggest race in Colorado in October?
- By estimated field size, the largest event is the Rock 'n' Roll Denver Marathon & Half Marathon, with about 7,000 runners across all of its distances.
Search every race in Colorado
Filter by month, distance, course profile and field size, save races to a shortlist and compare them side by side in the interactive search.