Colorado Half Marathon Calendar 2025-2026

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Explore the best half marathons in Colorado for 2025-2026! Our updated list features 89 exciting races across the region. Find your next race in Colorado below and join the running community at these great events!

April 2026
Apr
12
Sunday

Platte River Half-Marathon

13 mi
Apr
18
Saturday

All-Out Beat the Heat

5 km 10 km 13 mi
Apr
19
Sunday

Horsetooth Half Marathon

13 mi
Apr
25
Saturday

Runs With Scissors Races

13 mi 26 mi 50 km
May 2026
May
3
Sunday

Colorado Marathon

5 km 10 km 13 mi 26 mi
May
9
Saturday

Valkyrie Trail Race

Trail Run 4 mi 8 mi ... 26 mi 50 km
May
16
Saturday

Endure Trail Runs

Backyard Ultra 10 km 13 mi 26 mi 12 hr
May
16-17
Sa - Su

Denver Colfax Marathon

10 mi 13 mi 26 mi
May
30-31
Sa - Su

Colorado Springs Spartan Trifecta Weekend

Obstacle Run 5 km 10 km 21 km 50 km
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