Find upcoming endurance races in Colorado, laid out by month. Scan the dates, line them up against your training, and find the race that fits your season.
Endurance Grid lists 361 races in Colorado, from July 2026 to August 2027 across 98 cities.
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The lay of the land
Colorado runs a year-round race calendar, so there’s almost always a race near you. The calendar is busiest in September, August, and October, with races most often held in Denver, Colorado Springs, Centennial, and Littleton.
Races in Colorado run from the high peaks and passes of the Rocky Mountains to the short-grass plains stretching east of Denver, with dry mesa country and canyons in the west. That means thin-air mountain trail ultras, resort-town road races, and flat, fast prairie courses within the same state.
Conditions vary widely by region across Colorado, so weather lives where it’s accurate — each race page shows its typical race-day high, low, and rain chance from NOAA climate normals for that venue and date.
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Frequently Asked Questions (FAQs)
Endurance races in Colorado happening in the next 7 days, in date order. Browse what’s coming up and sign up soon.