Colorado Triathlon Calendar 2025-2026

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Explore the best triathlons in Colorado for 2025-2026! Our updated list features 262 exciting races across the region. Find your next race in Colorado below and join the running community at these great events!

April 2026
Apr
25
Saturday

SOAR 5k

3 mi
Apr
26
Sunday

Unicorn 5k

2 mi 5 km
May 2026
May
2
Saturday

Greenland Trail Races

Trail Run 4 mi 8 mi 25 km 50 km
May
2
Saturday

Niwot's Challenge

Trail Run 24 mi 50 mi 100 mi
May
2
Saturday

Take 5 in The Garden

Trail Run 5 km 5 mi
May
2
Saturday

The Best Races - Centennial

5 km 10 km 13 mi
May
2
Saturday

Collegiate Peaks Trail Run

Trail Run 25 mi 50 mi
May
3
Sunday

Colorado Marathon

5 km 10 km Half Marathon Marathon
May
3
Sunday

The Pilgrimage

Trail Run 7 mi 11 mi 12 mi 13 mi
May
3
Sunday

Longmont Half

5 km Half Marathon
May
9
Saturday

Valkyrie Trail Race

Trail Run 4 mi 8 mi ... Marathon 50 km
May
9-10
Sa - Su

Adventure Fest at 18 Road

Trail Run Half Marathon 22 km 50 km
May
9-10
Sa - Su

Quad Rock 50

Trail Run 25 mi 50 mi
May
10
Sunday

Colorado Women's Classic

5 km 10 km 10 mi
May
10
Sunday

Fruita Trail Half Marathon

Trail Run 14 mi
May
15-17
Fr - Su

Denver Colfax Marathon

10 mi 13 mi 26 mi
May
16
Saturday

Endure Trail Runs

Backyard Ultra 10 km Half Marathon Marathon 12 hr
May
16
Saturday

Ram Party Trail Runs

Trail Run 15 km 24 km ... 60 km 55 mi
May
16
Saturday

Sky Pilots Ouray Backyard Ultra

Backyard Ultra 4 mi
May
16
Saturday

Memorial Day Run & March

5 km 10 km 30 km
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