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Colorado Running Calendar 2025-2026

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Monthly updates for Colorado

Get new running races (and updates) in your inbox every month.

Explore the best running races in Colorado for 2025-2026! Our updated list features 290 exciting races across the region. Find your next race in Colorado below and join the running community at these great events!

Half Marathons Marathons Trail Runs Triathlons
December 2025
Dec
31
We

Resolution Run - Fort Collins

5 km
January 2026
Jan
1
Th

Resolute Runner 5k

5 km
Jan
1
Th

Rescue Run

5 km 10 km
Jan
1
Th

Durango Resolution Run 5K

5 km
Jan
1
Th

Far Resolution Run

5 km 10 km
Jan
3
Sa

The Best Races - Centennial

5 km 10 km 13 mi
Jan
10
Sa

Polar Prowl

3 mi 6 mi 13 mi
Jan
10
Sa

Sentinel Flurry

5 km
Jan
17
Sa

The Best Races - Centennial

5 km 10 km 13 mi
Jan
18
Su

Arctic Prairie Dog Half Marathon

5 km 10 km
Jan
18
Su

Polar Bear 5K

5 km
Jan
18
Su

Colorado Cold Rush

5 km 10 km
Jan
24-25
Sa - Su

USCSA Cross Country Ski Racing Festival

Trail Run 3 km 8 km 15 km
Jan
24
Sa

Rio Frio on Ice

Trail Run 5 km
Jan
24
Sa

12 Hours of Sunlight

Backyard Ultra
Jan
24
Sa

Chilly Willy Half Marathon-Colorado Springs

5 km 10 km Half Marathon
Jan
24
Sa

Polar Bear Run and Plunge

5 km
Jan
25
Su

Yeti Chase 10k

5 km 10 km
Jan
25
Su

Freakin Freezin 5K - Denver

Trail Run 5 km
Jan
31
Sa

Sourdough Snowshoe Race

Trail Run 18 km 30 km