10K races in Colorado, United States — 2026 running calendar

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

Windsor, Colorado, United States

Oct 4, 2026 (Sun)

$20.00 - $115.00

Running

Marathon Half-Marathon 10K 5K +1

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

Centennial, Colorado, United States

Oct 10, 2026 (Sat) – Nov 28, 2026

$30.00 - $45.00

Running

5K 10K Half-Marathon 1.6K +8

Breckenridge RunFest

Breckenridge, Colorado, United States

Oct 10, 2026 (Sat) – Oct 11, 2026

$25.00 - $120.00

Running

10K 5K 1.6K Marathon +1

Your Story Isn't Over 5k/10k/Kids 1-Mile

Littleton, Colorado, United States

Oct 11, 2026 (Sun)

$20.00 - $40.00

Running

1.6K 10K 5K

Ghosts and Goblins 5K/10K

Denver, Colorado, United States

Oct 25, 2026 (Sun)

$33.00 - $43.00

Running

5K 10K

Spooky Sprint - Colorado Springs

Colorado Springs, Colorado, United States

Oct 31, 2026 (Sat)

$22.00 - $30.00

Running

1.6K 5K 10K

Halloween Trick or Trot Run 5K/10K/13.1 DENVER/AURORA

Centennial, Colorado, United States

Oct 31, 2026 (Sat)

$30.00 - $45.00

Running

5K 10K Half-Marathon 1.6K +2

PB&J Fuel Run 5K/10K/13.1 DENVER/AURORA

Centennial, Colorado, United States

Oct 31, 2026 (Sat)

$30.00 - $45.00

Running

5K 10K Half-Marathon 1.6K +2

All-Out Kooky-Spooky

Golden, Colorado, United States

Nov 1, 2026 (Sun)

$25.00 - $70.00

Running

Half-Marathon 10K 5K +2

Feet for Justice Run

Denver, Colorado, United States

Nov 1, 2026 (Sun)

$10.00 - $35.00

Running

10K 5K Kids Run

City Park Classic (5k/10k & 1 Mile Walk of Hope for Pancreatic Cancer Research)

Denver, Colorado, United States

Nov 7, 2026 (Sat)

$20.00 - $60.00

Running, Walking

5K 10K 1.6K

Alamosa Veterans Memorial Park Race

Alamosa, Colorado, United States

Nov 7, 2026 (Sat)

$20.00 - $35.00

Running

5K 10K