Running Race Calendar in Colorado, United States near Thornton

Treat Trot - Denver

Thornton, Colorado, United States

13 Jun, 2026 (Sat)

$22.00 - $44.00

Running

1.6K 5K 10K 15K

Unicorn 5k (North)

Thornton, Colorado, United States

20 Jun, 2026 (Sat)

$24.00 - $51.00

Running

5K 1K

Summer Sizzler- Denver

Thornton, Colorado, United States

08 Aug, 2026 (Sat)

$22.00 - $36.00

Running

1.6K 5K 10K 15K

Rmrr Fall Marathon Training Series

Thornton, Colorado, United States

23 Aug, 2026 (Sun) – 20 Sep, 2026

$20.00 - $75.00

Running

16.1K 32.2K

RMRR September Trophy Series

Thornton, Colorado, United States

13 Sep, 2026 (Sun)

$10.00

Running

10K 5K

Rmrr Fall Marathon Training Series #2

Thornton, Colorado, United States

13 Sep, 2026 (Sun)

$20.00 - $30.00

Running

20K 30K

Rmrr Fall Marathon Training Series #3

Thornton, Colorado, United States

27 Sep, 2026 (Sun)

$20.00 - $30.00

Running

16.1K 32.2K

I Can 5k

Thornton, Colorado, United States

03 Oct, 2026 (Sat)

Free

Running

5K +2

I Ain't Scared (of 5k)

Thornton, Colorado, United States

31 Oct, 2026 (Sat)

$40.00

Running

5K

WinterFest 5k & Fun Run

Thornton, Colorado, United States

12 Dec, 2026 (Sat)

$25.00

Running

5K

Memorial Day 5K Virtual Run - Thornton

Thornton, Colorado, United States

23 May, 2026 (Sat) – 25 May, 2026

Running

5K

2026 Mother's Day Virtual 5k - Thornton

Thornton, Colorado, United States

09 May, 2026 (Sat) – 11 May, 2026

Running

5K