Race Calendar in Colorado, United States

Outlast Denver

Littleton, Colorado, United States

03 Oct, 2026 (Sat)

$90.00

Trail running

29K

Homecoming 5K - Colorado State University

Fort Collins, Colorado, United States

03 Oct, 2026 (Sat)

$25.00 - $30.00

Running

5K +1

Lafayette Music Fest -5K - 10K

Lafayette, Colorado, United States

03 Oct, 2026 (Sat)

$45.00 - $65.00

Running

10K 5K

Rim to Rim Royal Gorge Races: 5K Road Run, Trail 8 Mile, Trail Half Marathon

Canon City, Colorado, United States

03 Oct, 2026 (Sat)

$40.00 - $80.00

Running

5K 12.9K Half-Marathon 10K +2

Splashland Triathlon

Alamosa, Colorado, United States

03 Oct, 2026 (Sat)

Big Waves Family 5K run/walk Presented by Brumate

Westminster, Colorado, United States

03 Oct, 2026 (Sat)

$40.00

Running

5K

HRCA Wildcat Mountain Trail Races

Littleton, Colorado, United States

03 Oct, 2026 (Sat)

$45.00 - $55.00

Trail running

16.1K 10K

RMRR October Trophy Series

Aurora, Colorado, United States

04 Oct, 2026 (Sun)

$10.00

Running

12.9K 5K

OTILLO Swimrun Colorado

Fort Collins, Colorado, United States

04 Oct, 2026 (Sun)

Windsor Marathon, Half Marathon, 10k, 5k & 1 Mile Run

Windsor, Colorado, United States

04 Oct, 2026 (Sun)

$20.00 - $115.00

Running

Marathon Half-Marathon 10K 5K +1

Rubey Rescue Run

Aspen, Colorado, United States

04 Oct, 2026 (Sun)

$60.38

Trail running

5K

Coffee Lovers Run 5K/10K/13.1 DENVER/AURORA

Centennial, Colorado, United States

10 Oct, 2026 (Sat) – 28 Nov, 2026

$30.00 - $45.00

Running

5K 10K Half-Marathon 1.6K +8